diff --git a/Cargo.lock b/Cargo.lock
index ade3a5a..1815ac7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1508,6 +1508,8 @@ dependencies = [
  "image",
  "log",
  "muda",
+ "objc2 0.6.5",
+ "objc2-app-kit 0.3.2",
  "pollster 1.0.1",
  "rfd",
  "serde_json",
diff --git a/ROADMAP.md b/ROADMAP.md
index 94ae973..90aabd4 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -2,7 +2,7 @@
 
 **Stage: alpha** · next: beta, ~25 points of "ready for real work" and ~160–240 h away
 
-> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (direct desktop printing through craft-print) · **Target:** Microsoft Excel (Microsoft 365)
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (editable ink survives XLSX saves) · **Target:** Microsoft Excel (Microsoft 365)
 
 GridCraft aims at full Microsoft Excel parity, and at being better in places: faster, open (XLSX
 is the native format), fully scriptable by agents (MCP, control channel, CLI), and on the web.
@@ -133,6 +133,14 @@ Ranked; estimates in Opus 5.5 agent-hours. Detail and the full beta-gate list in
 | Date | What landed |
 |---|---|
 | 2026-10-12 | CSV and tab-separated export is capped at 512 MiB: a sheet whose used range would expand to more (two cells far apart, such as A1 and XFD1048576, are 16 GiB of commas) is refused with the rows, columns and limit, before anything is allocated or written (#528) |
+| 2026-10-12 | PDF writer hardening: text width cannot overflow, all-zero dash arrays and negative or NaN stroke widths are sanitised, non-finite sizes and positions draw nothing (#812) |
+| 2026-10-12 | PDF export writes the document title and author as UTF-16BE when they are not ASCII, so viewers show accents, currency signs and non-Latin text correctly (#813) |
+| 2026-10-12 | `TEXT()` over a range and chart labels parse each number format code once instead of once per value (#806) |
+| 2026-10-12 | SUBTOTAL(109) over hidden rows recalculates after Row Height, AutoFit Row Height and Ungroup reveal rows (found by the command-sequence fuzz) |
+| 2026-10-12 | Page Layout view: drag the margin edges on the rulers to set the page margins (resize cursor, live preview, value tooltip, one undo step, Esc cancels) (#792) |
+| 2026-10-12 | Forecast Sheet gets Forecast Start: begin the forecast inside the history to compare it with the actuals (#785) |
+| 2026-10-12 | Ink strokes save as unfilled DrawingML paths and reopen as editable ink with their points, colour and width; icons in #551 remain a follow-up |
+| 2026-10-12 | The selection outline stays visible when extended to the last row (Ctrl+Shift+Down): its sides are cut to the viewport instead of stroking a 20-million-point rectangle (#687) |
 | 2026-10-12 | File › Print selects a system printer, copies, duplex and grayscale, submits PDF jobs through craft-print on a worker and shows spooler errors; browser printing and PDF export remain available |
 | 2026-10-11 | Command-sequence fuzzing: random command sequences checked against undo/redo, XLSX round-trip and full recalculation; fixes for the table, legacy-array, spill, AutoSum, Watch Window and sheet-copy bugs it found |
 | 2026-10-11 | Password-protected workbooks open: GridCraft asks for the password and decrypts Agile and Standard encryption (#11) |
@@ -180,6 +188,8 @@ Ranked; estimates in Opus 5.5 agent-hours. Detail and the full beta-gate list in
 | Date | Change | Summary |
 |---|---|---|
 | 2026-10-12 | trivial | Progress log: CSV export size cap (#528) |
+| 2026-10-12 | minor | Progress log: margins dragged on the Page Layout rulers (#792) |
+| 2026-10-12 | minor | Ink preservation across XLSX save/reopen (ink portion of #551) |
 | 2026-10-12 | minor | Desktop File > Print now discovers printers and submits PDF jobs through pinned craft-print with printer choice, copies, duplex and grayscale; browser printing and PDF export remain available. Remaining print parity includes page ranges and driver-specific tray/options UI; physical printer fidelity needs hardware validation. |
 | 2026-10-11 | minor | Password-encrypted workbooks open (#11); progress log row |
 | 2026-10-11 | minor | Forecast Sheet (#322); progress log row |
diff --git a/apps/gridcraft-cli/src/check.rs b/apps/gridcraft-cli/src/check.rs
index 9fc81e3..d514b1e 100644
--- a/apps/gridcraft-cli/src/check.rs
+++ b/apps/gridcraft-cli/src/check.rs
@@ -97,6 +97,9 @@ pub struct CalcReport {
     /// aren't results, so every formula counts as no oracle.
     pub stale_cache: bool,
     pub volatile: usize,
+    /// Matched cells whose producer saved GridCraft's TRUE or FALSE as the number 1 or 0 (no
+    /// `t="b"`, as Business Central's Excel exports do); counted in `matched` too.
+    pub bool_as_number: usize,
     /// The first `max_report` mismatches, primary ones first.
     pub mismatches: Vec<Mismatch>,
     pub functions: BTreeMap<String, FnStat>,
@@ -347,6 +350,13 @@ fn cell_name(wb: &Workbook, (sheet, c): Key) -> String {
     format!("{}!{}", quote_sheet(name), c.a1())
 }
 
+/// Whether the producer cached GridCraft's logical result as the number 1 or 0. Excel types a
+/// logical result `t="b"`; a writer that leaves the type out (`<c><f>TRUE()</f><v>1</v></c>`, as
+/// Business Central's "Open in Excel" exports do) stores the same value, read back as a number.
+pub fn bool_cached_as_number(expected: &Value, actual: &Value) -> bool {
+    matches!((expected, actual), (Value::Number(n), Value::Bool(b)) if *n == if *b { 1.0 } else { 0.0 })
+}
+
 /// Whether GridCraft's `actual` agrees with the producer's `expected`.
 pub fn values_match(expected: &Value, actual: &Value, tolerance: f64) -> bool {
     match (expected, actual) {
@@ -458,7 +468,11 @@ pub fn oracle(cached: &Workbook, fresh: &Workbook, calc: &Calc, trust_cache: boo
                 }
                 None => vec!["(unparsed)".to_string()],
             };
-            let ok = values_match(&cell.value, &actual, opts.tolerance);
+            let bool_as_number = bool_cached_as_number(&cell.value, &actual);
+            let ok = bool_as_number || values_match(&cell.value, &actual, opts.tolerance);
+            if bool_as_number {
+                r.bool_as_number += 1;
+            }
             for n in &funcs {
                 let st = r.functions.entry(n.clone()).or_default();
                 st.checked += 1;
@@ -559,6 +573,14 @@ fn diff_sets(d: &mut Diffs, sheet: &str, a: &BTreeSet<String>, b: &BTreeSet<Stri
     }
 }
 
+/// A sheet's conditional-format rules in precedence order, as comparable text. The priority number
+/// itself is left out, so renumbering without changing the order isn't a difference.
+fn cond_format_list(s: &Sheet) -> Vec<String> {
+    let mut cfs: Vec<_> = s.cond_formats.iter().collect();
+    cfs.sort_by_key(|c| c.priority);
+    cfs.iter().map(|c| format!("{:?} {:?} stopIfTrue={}", c.ranges, c.rule, c.stop_if_true)).collect()
+}
+
 fn diff_count(d: &mut Diffs, sheet: &str, a: usize, b: usize) {
     if a != b {
         d.push(|| format!("{sheet}: {a} → {b}"));
@@ -634,7 +656,12 @@ pub fn diff_workbooks(a: &Workbook, b: &Workbook, opts: &Options) -> Vec<Categor
                 .collect()
         };
         diff_sets(&mut tables, &name, &set(&table_list, sa), &set(&table_list, sb));
-        diff_count(&mut cond_formats, &name, sa.cond_formats.len(), sb.cond_formats.len());
+        let (cfa, cfb) = (cond_format_list(sa), cond_format_list(sb));
+        if cfa.len() != cfb.len() {
+            cond_formats.push(|| format!("{name}: {} → {}", cfa.len(), cfb.len()));
+        } else if let Some((x, y)) = cfa.iter().zip(&cfb).find(|(x, y)| x != y) {
+            cond_formats.push(|| format!("{name}: {x} → {y}"));
+        }
         diff_count(&mut validations, &name, sa.validations.len(), sb.validations.len());
         let chart_list = |s: &Sheet| s.charts.iter().map(|c| format!("{:?} ({} series)", c.kind, c.series.len())).collect::<Vec<_>>();
         let (ca, cb) = (chart_list(sa), chart_list(sb));
@@ -901,6 +928,7 @@ struct Totals {
     mismatched: usize,
     no_oracle: usize,
     volatile: usize,
+    bool_as_number: usize,
     round_trip_failed: usize,
     round_trip_differing: usize,
     categories: BTreeMap<&'static str, usize>,
@@ -922,6 +950,7 @@ fn totals(reports: &[FileReport]) -> Totals {
         t.mismatched += r.calc.mismatched;
         t.no_oracle += r.calc.no_oracle;
         t.volatile += r.calc.volatile;
+        t.bool_as_number += r.calc.bool_as_number;
         if r.round_trip.error.is_some() {
             t.round_trip_failed += 1;
         }
@@ -982,7 +1011,8 @@ pub fn report_json(reports: &[FileReport], opts: &Options) -> Json {
                 "warnings": r.warnings,
                 "calc": {
                     "formulaCells": c.formula_cells, "checked": c.checked, "matched": c.matched, "mismatched": c.mismatched,
-                    "noOracle": c.no_oracle, "staleCache": c.stale_cache, "volatile": c.volatile, "mismatches": mismatches, "functions": functions_json(&c.functions),
+                    "noOracle": c.no_oracle, "staleCache": c.stale_cache, "volatile": c.volatile, "boolAsNumber": c.bool_as_number,
+                    "mismatches": mismatches, "functions": functions_json(&c.functions),
                     "signatures": c.signatures,
                 },
                 "roundTrip": {"error": r.round_trip.error, "differing": r.round_trip.differing(), "categories": categories},
@@ -996,7 +1026,7 @@ pub fn report_json(reports: &[FileReport], opts: &Options) -> Json {
         "files": files,
         "totals": {
             "files": t.files, "opened": t.opened, "failedToOpen": t.failed, "formulaCells": t.formula_cells, "checked": t.checked,
-            "matched": t.matched, "mismatched": t.mismatched, "noOracle": t.no_oracle, "volatile": t.volatile,
+            "matched": t.matched, "mismatched": t.mismatched, "noOracle": t.no_oracle, "volatile": t.volatile, "boolAsNumber": t.bool_as_number,
             "roundTripFailed": t.round_trip_failed, "roundTripDiffering": t.round_trip_differing, "categoriesDiffering": t.categories,
         },
         "functions": functions_json(&t.functions),
@@ -1035,6 +1065,9 @@ fn print_human(reports: &[FileReport], opts: &Options) {
         if c.stale_cache {
             outln!("  (the producer asked for a full recalculation on load: its cached values aren't results)");
         }
+        if c.bool_as_number > 0 {
+            outln!("  ({} matched TRUE/FALSE results were saved by the producer as 1/0, without t=\"b\")", c.bool_as_number);
+        }
         for m in &c.mismatches {
             let tag = if m.primary { "mismatch" } else { "  (downstream)" };
             outln!(
@@ -1131,6 +1164,9 @@ fn print_human(reports: &[FileReport], opts: &Options) {
         t.no_oracle,
         t.volatile
     );
+    if t.bool_as_number > 0 {
+        outln!("booleans saved as 1/0 by the producer: {} (counted as matched)", t.bool_as_number);
+    }
     let cats: Vec<String> = t.categories.iter().map(|(c, n)| format!("{c} {n}")).collect();
     outln!(
         "round trip: {} of {} files differ{}{}",
@@ -1235,6 +1271,31 @@ mod tests {
         assert_eq!(check(&wb, &Options { tolerance: 1e-12, ..Default::default() }).calc.mismatched, 1);
     }
 
+    /// Business Central writes TRUE and FALSE as `<c><f>TRUE()</f><v>1</v></c>`, without `t="b"`:
+    /// the cache holds the right value under a number type, so it matches and is counted apart.
+    #[test]
+    fn booleans_cached_as_numbers_match_and_are_counted_apart() {
+        let wb = book(&[
+            ("A1", "=TRUE()", n(1.0)),
+            ("B1", "=FALSE()", n(0.0)),
+            ("C1", "=TRUE()", Value::Bool(true)),
+            ("D1", "=1=1", n(0.0)),
+            ("E1", "=TRUE()+0", n(1.0)),
+        ]);
+        let r = check(&wb, &Options::default());
+        assert_eq!((r.calc.checked, r.calc.matched, r.calc.mismatched), (5, 4, 1));
+        // A cached 0 for TRUE is still a mismatch, and a number result is compared as a number.
+        assert_eq!(r.calc.mismatches[0].cell, "Sheet1!D1");
+        assert_eq!(r.calc.signatures.get("number → bool"), Some(&1));
+        assert_eq!(r.calc.bool_as_number, 2);
+        let v = report_json(std::slice::from_ref(&r), &Options::default());
+        assert_eq!((v["files"][0]["calc"]["boolAsNumber"].clone(), v["totals"]["boolAsNumber"].clone()), (json!(2), json!(2)));
+        assert!(bool_cached_as_number(&n(1.0), &Value::Bool(true)));
+        assert!(!bool_cached_as_number(&n(1.0), &Value::Bool(false)));
+        assert!(!bool_cached_as_number(&n(2.0), &Value::Bool(true)));
+        assert!(!bool_cached_as_number(&Value::Bool(true), &n(1.0)));
+    }
+
     #[test]
     fn missing_cached_values_and_volatile_formulas_are_skipped() {
         let wb =
@@ -1303,6 +1364,27 @@ mod tests {
         assert_eq!(get("tables").diffs, 0);
     }
 
+    #[test]
+    fn diff_detects_changed_cond_format_rule() {
+        use gridcraft_engine::model::{CfRule, CfValueKind, Color, CondFormat};
+        let bar = |gradient: bool, priority: u32| CondFormat {
+            ranges: vec![gridcraft_engine::core::RangeRef::parse("A1").unwrap()],
+            rule: CfRule::DataBar { min: CfValueKind::Min, max: CfValueKind::Max, color: Color::Rgb(0x638EC6), gradient, show_value: true },
+            priority,
+            stop_if_true: false,
+        };
+        let with = |cf: CondFormat| {
+            let mut wb = book(&[("A1", "2", n(2.0))]);
+            wb.sheet_mut(0).unwrap().cond_formats.push(cf);
+            wb
+        };
+        let diffs =
+            |a: &Workbook, b: &Workbook| diff_workbooks(a, b, &Options::default()).into_iter().find(|c| c.name == "condFormats").unwrap().diffs;
+        assert_eq!(diffs(&with(bar(false, 1)), &with(bar(true, 1))), 1);
+        assert_eq!(diffs(&with(bar(true, 1)), &with(bar(true, 1))), 0);
+        assert_eq!(diffs(&with(bar(true, 1)), &with(bar(true, 5))), 0);
+    }
+
     fn zip_of(parts: &[(&str, &str)]) -> Vec<u8> {
         let mut z = zip::ZipWriter::new(Cursor::new(Vec::new()));
         for (name, body) in parts {
@@ -1362,7 +1444,19 @@ mod tests {
         assert_eq!(keys(f), set(&["path", "opened", "error", "warnings", "calc", "roundTrip"]));
         assert_eq!(
             keys(&f["calc"]),
-            set(&["formulaCells", "checked", "matched", "mismatched", "noOracle", "staleCache", "volatile", "mismatches", "functions", "signatures"])
+            set(&[
+                "formulaCells",
+                "checked",
+                "matched",
+                "mismatched",
+                "noOracle",
+                "staleCache",
+                "volatile",
+                "boolAsNumber",
+                "mismatches",
+                "functions",
+                "signatures"
+            ])
         );
         assert_eq!(f["calc"]["signatures"], json!({"number → number": 1}));
         assert_eq!(keys(&f["calc"]["mismatches"][0]), set(&["cell", "formula", "expected", "actual", "kind", "functions", "primary"]));
@@ -1401,6 +1495,7 @@ mod tests {
                 "mismatched",
                 "noOracle",
                 "volatile",
+                "boolAsNumber",
                 "roundTripFailed",
                 "roundTripDiffering",
                 "categoriesDiffering"
diff --git a/apps/gridcraft-web/Cargo.toml b/apps/gridcraft-web/Cargo.toml
index 0f69e38..eac6c13 100644
--- a/apps/gridcraft-web/Cargo.toml
+++ b/apps/gridcraft-web/Cargo.toml
@@ -26,4 +26,4 @@ rfd = { workspace = true }
 wasm-bindgen = "0.2"
 wasm-bindgen-futures = "0.4"
 js-sys = "0.3"
-web-sys = { version = "0.3", features = ["Window", "Document", "Element", "HtmlElement", "HtmlCanvasElement", "HtmlAnchorElement", "HtmlIFrameElement", "Blob", "BlobPropertyBag", "Url", "Location", "CssStyleDeclaration", "Clipboard", "ClipboardItem", "Navigator"] }
+web-sys = { version = "0.3", features = ["Window", "Document", "Element", "HtmlElement", "HtmlCanvasElement", "HtmlAnchorElement", "HtmlIFrameElement", "Blob", "BlobPropertyBag", "Url", "Location", "CssStyleDeclaration", "Clipboard", "ClipboardItem", "Navigator", "MessageEvent", "UrlSearchParams"] }
diff --git a/apps/gridcraft-web/src/host.rs b/apps/gridcraft-web/src/host.rs
new file mode 100644
index 0000000..2286023
--- /dev/null
+++ b/apps/gridcraft-web/src/host.rs
@@ -0,0 +1,166 @@
+//! The `postMessage` bridge to a same-origin parent page (`?host=parent`), for pages that embed
+//! GridCraft in an `<iframe>` (such as a Nextcloud app). Messages are plain objects with a `type`:
+//!
+//! - `gridcraft:ready` (to the parent): `{ version }`, the app is listening; send a file now.
+//! - `gridcraft:open` (from the parent): `{ name, bytes }`, bytes an `ArrayBuffer` or
+//!   `Uint8Array`. It opens like a workbook picked with File › Open or dropped on the window.
+//! - `gridcraft:save` (to the parent): `{ name, bytes }` (a transferred `ArrayBuffer`) for every
+//!   file GridCraft would otherwise download: Save and Save As (an .xlsx workbook) and Export
+//!   as PDF. The parent stores it and reports failures itself.
+//! - `gridcraft:dirty` (to the parent): `{ dirty }` whenever unsaved changes appear or go away.
+//! - `gridcraft:failed` (to the parent): `{ error }` when the app couldn't start.
+//!
+//! Only the parent window on the page's own origin is heard or answered. In host mode the page
+//! starts with an empty workbook instead of a sample, and the parent guards leaving the page.
+
+use std::cell::{Cell, RefCell};
+use std::rc::Rc;
+
+use gridcraft_ui_egui::{Inbox, Services, SheetApp};
+use wasm_bindgen::JsCast as _;
+use wasm_bindgen::JsValue;
+use wasm_bindgen::closure::Closure;
+
+/// Saving one of these hands the whole workbook to the parent, which stores it: the workbook
+/// counts as saved under that name, as it would after Save on the desktop.
+const WORKBOOK_EXTS: &[&str] = &["xlsx"];
+
+/// The longest user name taken from `?author=`.
+const MAX_AUTHOR_CHARS: usize = 200;
+
+#[derive(Clone)]
+pub struct Bridge {
+    window: web_sys::Window,
+    parent: web_sys::Window,
+    origin: String,
+    /// Names of the files handed to the parent since the last frame.
+    saved: Rc<RefCell<Vec<String>>>,
+    /// The unsaved-changes state last reported to the parent.
+    reported: Rc<Cell<Option<bool>>>,
+}
+
+impl Bridge {
+    /// `None` when the page isn't framed (there is no parent to talk to).
+    pub fn new() -> Option<Self> {
+        let window = web_sys::window()?;
+        let parent = window.parent().ok().flatten()?;
+        if js_sys::Object::is(&parent, &window) {
+            return None;
+        }
+        let origin = window.location().origin().ok()?;
+        Some(Self { window, parent, origin, saved: Rc::default(), reported: Rc::default() })
+    }
+
+    /// Send saved and exported files to the parent instead of downloading them, and hear files
+    /// from it.
+    pub fn connect(&self, services: &mut Services, inbox: Inbox, ctx: egui::Context) {
+        self.listen(inbox, ctx);
+        let bridge = self.clone();
+        services.download = Some(Box::new(move |name: &str, bytes: &[u8]| {
+            if let Err(e) = bridge.post_save(name, bytes) {
+                log::error!("couldn't hand {name} to the page: {e}");
+            }
+        }));
+    }
+
+    /// `?author=`: the host's name for the user signs new notes and comments.
+    pub fn set_author(app: &mut SheetApp, author: &str) {
+        let author: String = author.trim().chars().take(MAX_AUTHOR_CHARS).collect();
+        if !author.is_empty() {
+            app.session.prefs.user_name = author;
+        }
+    }
+
+    pub fn post_ready(&self) {
+        self.send(&[("type", "gridcraft:ready".into()), ("version", env!("CARGO_PKG_VERSION").into())]);
+    }
+
+    pub fn post_failed(&self, error: &str) {
+        self.send(&[("type", "gridcraft:failed".into()), ("error", error.into())]);
+    }
+
+    /// After each frame: a workbook handed to the parent this frame counts as saved under the
+    /// name it was saved as, and the parent hears when unsaved changes appear or go away.
+    pub fn sync(&self, app: &mut SheetApp) {
+        let saved = std::mem::take(&mut *self.saved.borrow_mut());
+        if let Some(name) = saved.iter().rev().find(|name| is_workbook(name))
+            && let Some(doc) = app.session.active_mut()
+        {
+            doc.saved = doc.wb.clone();
+            if doc.path.is_none() {
+                doc.title = name.clone();
+            }
+        }
+        let dirty = app.session.documents().iter().any(|d| d.is_dirty());
+        if self.reported.get() != Some(dirty) && self.send(&[("type", "gridcraft:dirty".into()), ("dirty", dirty.into())]) {
+            self.reported.set(Some(dirty));
+        }
+    }
+
+    fn post_save(&self, path: &str, bytes: &[u8]) -> Result<(), String> {
+        let name = std::path::Path::new(path).file_name().map(|n| n.to_string_lossy().to_string()).unwrap_or_else(|| path.to_string());
+        let buffer = js_sys::Uint8Array::from(bytes).buffer();
+        let message = message(&[("type", "gridcraft:save".into()), ("name", name.as_str().into()), ("bytes", buffer.clone().into())])
+            .ok_or_else(|| "couldn't build the message".to_string())?;
+        self.parent
+            .post_message_with_transfer(&message, &self.origin, &js_sys::Array::of1(&buffer))
+            .map_err(|e| e.as_string().unwrap_or_else(|| format!("{e:?}")))?;
+        self.saved.borrow_mut().push(name);
+        Ok(())
+    }
+
+    fn listen(&self, inbox: Inbox, ctx: egui::Context) {
+        let parent = self.parent.clone();
+        let origin = self.origin.clone();
+        let on_message = Closure::<dyn FnMut(web_sys::MessageEvent)>::new(move |event: web_sys::MessageEvent| {
+            if event.origin() != origin || !event.source().is_some_and(|s| js_sys::Object::is(&s, &parent)) {
+                return;
+            }
+            let data = event.data();
+            if string(&data, "type").as_deref() != Some("gridcraft:open") {
+                return;
+            }
+            let name = string(&data, "name").filter(|n| !n.trim().is_empty()).unwrap_or_else(|| "Book.xlsx".to_string());
+            let Some(bytes) = bytes(&data) else { return };
+            inbox.lock().unwrap_or_else(|e| e.into_inner()).push((name, bytes));
+            ctx.request_repaint();
+        });
+        if self.window.add_event_listener_with_callback("message", on_message.as_ref().unchecked_ref()).is_ok() {
+            // The listener lives as long as the page.
+            on_message.forget();
+        }
+    }
+
+    /// Post a message to the parent; false if it couldn't be sent.
+    fn send(&self, fields: &[(&str, JsValue)]) -> bool {
+        message(fields).is_some_and(|m| self.parent.post_message(&m, &self.origin).is_ok())
+    }
+}
+
+fn is_workbook(name: &str) -> bool {
+    name.rsplit_once('.').is_some_and(|(_, ext)| WORKBOOK_EXTS.iter().any(|e| ext.eq_ignore_ascii_case(e)))
+}
+
+fn message(fields: &[(&str, JsValue)]) -> Option<js_sys::Object> {
+    let m = js_sys::Object::new();
+    for (key, value) in fields {
+        js_sys::Reflect::set(&m, &JsValue::from_str(key), value).ok()?;
+    }
+    Some(m)
+}
+
+fn string(data: &JsValue, key: &str) -> Option<String> {
+    js_sys::Reflect::get(data, &JsValue::from_str(key)).ok()?.as_string()
+}
+
+/// `bytes` as an `ArrayBuffer` or `Uint8Array`.
+fn bytes(data: &JsValue) -> Option<Vec<u8>> {
+    let bytes = js_sys::Reflect::get(data, &JsValue::from_str("bytes")).ok()?;
+    if let Some(array) = bytes.dyn_ref::<js_sys::Uint8Array>() {
+        Some(array.to_vec())
+    } else if bytes.is_instance_of::<js_sys::ArrayBuffer>() {
+        Some(js_sys::Uint8Array::new(&bytes).to_vec())
+    } else {
+        None
+    }
+}
diff --git a/apps/gridcraft-web/src/main.rs b/apps/gridcraft-web/src/main.rs
index 58c4f43..2920a87 100644
--- a/apps/gridcraft-web/src/main.rs
+++ b/apps/gridcraft-web/src/main.rs
@@ -8,9 +8,14 @@
 //! (bytes arrive asynchronously through `Services::inbox`); Save downloads the file; dropped
 //! files are read asynchronously.
 //!
-//! URL query flags: `?webgl` forces WebGL2; `?sample=sales|budget|grades` opens a sample.
+//! URL query flags: `?webgl` forces WebGL2; `?sample=sales|budget|grades` opens a sample;
+//! `?host=parent` (inside an `<iframe>`) talks to a same-origin parent page instead: it sends the
+//! workbook to open and stores what GridCraft saves (`host`), and `&author=` names the user for
+//! notes and comments.
 #![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
 
+#[cfg(target_arch = "wasm32")]
+mod host;
 #[cfg(target_arch = "wasm32")]
 mod web;
 
diff --git a/apps/gridcraft-web/src/web.rs b/apps/gridcraft-web/src/web.rs
index e1350a1..3856aaf 100644
--- a/apps/gridcraft-web/src/web.rs
+++ b/apps/gridcraft-web/src/web.rs
@@ -25,6 +25,10 @@ pub fn start() {
         {
             create.instance_descriptor.backends = eframe::wgpu::Backends::GL;
         }
+        // `?host=parent`: a same-origin page framing GridCraft (such as a Nextcloud app) opens
+        // workbooks in it and stores what it saves (`host`).
+        let bridge = if query_param("host").as_deref() == Some("parent") { crate::host::Bridge::new() } else { None };
+        let app_bridge = bridge.clone();
         let result = eframe::WebRunner::new()
             .start(
                 canvas,
@@ -32,13 +36,18 @@ pub fn start() {
                 Box::new(move |cc| {
                     let inbox: Inbox = Inbox::default();
                     let mut session = Session::new();
-                    let q = query();
+                    // In host mode the parent sends the workbook to edit; no sample meanwhile.
+                    let q = if app_bridge.is_some() { String::new() } else { query() };
                     if let Some(name) = q.split(['?', '&']).find_map(|kv| kv.strip_prefix("sample=")) {
                         let _ = session.execute("file.new", serde_json::json!({"sample": name}));
                     } else if q.contains("sample") {
                         let _ = session.execute("file.new", serde_json::json!({"sample": "sales"}));
                     }
-                    let mut app = SheetApp::new(session, services(inbox.clone(), cc.egui_ctx.clone()));
+                    let mut services = services(inbox.clone(), cc.egui_ctx.clone());
+                    if let Some(bridge) = &app_bridge {
+                        bridge.connect(&mut services, inbox.clone(), cc.egui_ctx.clone());
+                    }
+                    let mut app = SheetApp::new(session, services);
                     app.ui.system_theme = true;
                     // Follow the browser's language, except a CJK one: the web build has no system
                     // CJK fonts (none are bundled), so that interface would render as tofu.
@@ -50,10 +59,19 @@ pub fn start() {
                         app.ui.language = browser;
                     }
                     SheetApp::setup_context_for_language(&cc.egui_ctx, false, app.ui.language);
-                    Ok(Box::new(WebShell { app, inbox }))
+                    if let Some(bridge) = &app_bridge {
+                        if let Some(author) = query_param("author") {
+                            crate::host::Bridge::set_author(&mut app, &author);
+                        }
+                        bridge.post_ready();
+                    }
+                    Ok(Box::new(WebShell { app, inbox, bridge: app_bridge }))
                 }),
             )
             .await;
+        if let (Err(e), Some(bridge)) = (&result, &bridge) {
+            bridge.post_failed(&format!("{e:?}"));
+        }
         if let Some(el) = document.get_element_by_id(LOADING_ID) {
             match result {
                 Ok(()) => el.remove(),
@@ -67,9 +85,14 @@ fn query() -> String {
     web_sys::window().and_then(|w| w.location().search().ok()).unwrap_or_default()
 }
 
+fn query_param(key: &str) -> Option<String> {
+    web_sys::UrlSearchParams::new_with_str(&query()).ok()?.get(key)
+}
+
 struct WebShell {
     app: SheetApp,
     inbox: Inbox,
+    bridge: Option<crate::host::Bridge>,
 }
 
 impl eframe::App for WebShell {
@@ -98,6 +121,9 @@ impl eframe::App for WebShell {
 
     fn ui(&mut self, ui: &mut egui::Ui, _frame: &mut eframe::Frame) {
         self.app.ui(ui);
+        if let Some(bridge) = &self.bridge {
+            bridge.sync(&mut self.app);
+        }
     }
 }
 
diff --git a/apps/gridcraft/Cargo.toml b/apps/gridcraft/Cargo.toml
index c867d24..cd8311b 100644
--- a/apps/gridcraft/Cargo.toml
+++ b/apps/gridcraft/Cargo.toml
@@ -42,3 +42,13 @@ muda = { version = "0.21", default-features = false }
 # by PdfCraft and PhotoCraft) registers the handler (Objective-C interop needs unsafe, which our
 # workspace forbids) behind a safe API. Pinned exactly: review the diff before bumping.
 fmv-macos-events = "=0.1.0"
+
+# tests/mac_menu_appkit.rs: reads AppKit's menu bar back. Already in Cargo.lock (muda, winit);
+# pinned exactly to the same versions.
+[target.'cfg(target_os = "macos")'.dev-dependencies]
+objc2 = "=0.6.5"
+objc2-app-kit = { version = "=0.3.2", default-features = false, features = ["std", "NSApplication", "NSMenu", "NSMenuItem", "NSResponder"] }
+
+[[test]]
+name = "mac_menu_appkit"
+harness = false
diff --git a/apps/gridcraft/src/main.rs b/apps/gridcraft/src/main.rs
index 8093205..08737a3 100644
--- a/apps/gridcraft/src/main.rs
+++ b/apps/gridcraft/src/main.rs
@@ -135,10 +135,22 @@ fn save_prefs(app: &SheetApp) {
     }
 }
 
+/// Read the system clipboard through the shared handle, creating it on first use.
+fn read_clipboard<T>(
+    handle: &RefCell<Option<arboard::Clipboard>>,
+    read: impl FnOnce(&mut arboard::Clipboard) -> Result<T, arboard::Error>,
+) -> Option<T> {
+    let mut clipboard = handle.try_borrow_mut().ok()?;
+    if clipboard.is_none() {
+        *clipboard = arboard::Clipboard::new().ok();
+    }
+    read(clipboard.as_mut()?).ok()
+}
+
 fn services() -> Services {
     // Keep the owner alive: X11/Wayland serve clipboard data from this handle.
     let clipboard: Rc<RefCell<Option<arboard::Clipboard>>> = Rc::default();
-    let paste_clipboard = clipboard.clone();
+    let (html_clipboard, text_clipboard) = (clipboard.clone(), clipboard.clone());
     Services {
         copy_html: Some(Box::new(move |html, text| {
             let mut clipboard = clipboard.borrow_mut();
@@ -147,13 +159,8 @@ fn services() -> Services {
             }
             clipboard.as_mut().ok_or("clipboard unavailable")?.set_html(html, Some(text)).map_err(|e| e.to_string())
         })),
-        paste_html: Some(Box::new(move || {
-            let mut clipboard = paste_clipboard.try_borrow_mut().ok()?;
-            if clipboard.is_none() {
-                *clipboard = arboard::Clipboard::new().ok();
-            }
-            clipboard.as_mut()?.get().html().ok()
-        })),
+        paste_html: Some(Box::new(move || read_clipboard(&html_clipboard, |clipboard| clipboard.get().html()))),
+        paste_text: Some(Box::new(move || read_clipboard(&text_clipboard, |clipboard| clipboard.get_text()))),
         pick_open: Some(Box::new(|| {
             rfd::FileDialog::new()
                 .add_filter("Spreadsheets", &["xlsx", "xlsm", "xls", "xlsb", "ods", "csv", "tsv", "txt", "json"])
@@ -369,3 +376,32 @@ fn main() -> eframe::Result<()> {
     }
     result
 }
+
+#[cfg(test)]
+mod packaging_tests {
+    use gridcraft_engine::io::FileKind;
+
+    /// The text between `start` and `end` that follows each `marker` in `text`, sorted (e.g. the
+    /// `xlsb` in `Classes\.xlsb\OpenWithProgids`).
+    fn extensions(text: &str, marker: &str, start: &str, end: char) -> Vec<String> {
+        let mut v: Vec<String> = text.split(marker).skip(1).filter_map(|s| s.split_once(start)?.1.split(end).next()).map(str::to_string).collect();
+        v.sort();
+        v
+    }
+
+    /// macOS Open With (`CFBundleDocumentTypes`) offers GridCraft for the same files as Windows
+    /// Open with, and GridCraft opens each of them. #321 added `.xlsb` and `.ods` on Windows and
+    /// Linux only.
+    #[test]
+    fn macos_and_windows_offer_the_same_file_types() {
+        let plist = include_str!("../../../packaging/macos/Info.plist.in");
+        let wxs = include_str!("../../../packaging/windows/gridcraft.wxs");
+        let mac = extensions(plist, "<key>CFBundleTypeExtensions</key>", "<string>", '<');
+        let win = extensions(wxs, "Key=\"Software\\Classes\\.", "", '\\');
+        assert!(mac.iter().any(|e| e == "xlsx"), "Info.plist.in extensions not found: {mac:?}");
+        assert_eq!(mac, win);
+        for ext in &mac {
+            assert!(FileKind::from_path(&format!("book.{ext}")).is_some(), "GridCraft doesn't open .{ext}");
+        }
+    }
+}
diff --git a/apps/gridcraft/src/native_menu.rs b/apps/gridcraft/src/native_menu.rs
index b127543..6985af3 100644
--- a/apps/gridcraft/src/native_menu.rs
+++ b/apps/gridcraft/src/native_menu.rs
@@ -24,6 +24,7 @@ fn tree() -> Vec<(&'static str, Vec<Entry>)> {
                 ("Close", "file.close", Some("CMD+W")),
                 ("Save", "file.save", Some("CMD+S")),
                 ("Save As…", "file.saveAs", Some("CMD+SHIFT+S")),
+                ("Export as PDF…", "file.exportPdf", None),
                 ("Export as CSV…", "dialog:saveCopy:csv", None),
                 ("Save as Web Page…", "dialog:saveCopy:html", None),
                 ("-", "", None),
@@ -215,6 +216,7 @@ impl NativeMenu {
         ]);
         let _ = menu.append(&app_menu);
         let mut theme_items = Vec::new();
+        let mut window_menu = None;
         for (title, entries) in tree() {
             let sub = Submenu::new(title, true);
             for (label, id, acc) in entries {
@@ -237,8 +239,17 @@ impl NativeMenu {
                 let _ = sub.append(&item);
             }
             let _ = menu.append(&sub);
+            if title == "Window" {
+                window_menu = Some(sub);
+            }
         }
         menu.init_for_nsapp();
+        // NSApp's windowsMenu is where macOS adds Move & Resize, Fill and Center, the targets of the
+        // system tiling shortcuts (Fn+Ctrl+arrows, Fn+F). Only once the menu is NSApp's: muda looks
+        // the submenu up in the installed main menu.
+        if let Some(window) = window_menu {
+            window.set_as_windows_menu_for_nsapp();
+        }
         let (tx, rx) = channel();
         let ctx = ctx.clone();
         MenuEvent::set_event_handler(Some(move |e: MenuEvent| {
@@ -298,6 +309,8 @@ impl NativeMenu {
                 app.open_dialog(name, params);
             } else if id == "edit.copy" || id == "edit.cut" {
                 app.copy_to_clipboard(ctx, &id);
+            } else if id == "edit.paste" {
+                app.paste_from_clipboard();
             } else {
                 app.run_or_alert(&id, json!({}));
             }
@@ -315,6 +328,15 @@ impl NativeMenu {
 mod tests {
     use super::*;
 
+    #[test]
+    fn file_menu_has_export_as_pdf_dispatching_the_command() {
+        let tree = tree();
+        let (_, file) = tree.iter().find(|(title, _)| *title == "File").expect("File menu");
+        let item = file.iter().find(|e| e.0 == "Export as PDF…").expect("Export as PDF… in the File menu");
+        assert_eq!(item.1, "file.exportPdf");
+        assert!(gridcraft_engine::find_command("file.exportPdf").is_some());
+    }
+
     #[test]
     fn theme_choices_use_the_shared_preference_command() {
         let mut app = SheetApp::new(gridcraft_engine::Session::new(), Default::default());
diff --git a/apps/gridcraft/tests/mac_menu_appkit.rs b/apps/gridcraft/tests/mac_menu_appkit.rs
new file mode 100644
index 0000000..e713f66
--- /dev/null
+++ b/apps/gridcraft/tests/mac_menu_appkit.rs
@@ -0,0 +1,34 @@
+//! The macOS menu bar as AppKit sees it, on the main thread (`harness = false`): install it through
+//! the real muda backend (`src/native_menu.rs`) and read NSApp back. The Window menu must be NSApp's
+//! `windowsMenu`: that is where macOS adds Move & Resize, Fill and Center, the targets of the system
+//! window tiling shortcuts (Fn+Ctrl+arrows, Fn+F), and lists the open windows (#716).
+
+// The app's own module, built into this test (cargo builds harness = false tests with cfg(test), so its
+// unit tests compile here too without a harness to run them).
+#[cfg(target_os = "macos")]
+#[path = "../src/native_menu.rs"]
+#[allow(unused_imports, dead_code)]
+mod native_menu;
+
+#[cfg(target_os = "macos")]
+fn main() {
+    use objc2::MainThreadMarker;
+    use objc2_app_kit::NSApplication;
+
+    let mtm = MainThreadMarker::new().expect("harness = false runs on the main thread");
+    let nsapp = NSApplication::sharedApplication(mtm);
+    nsapp.finishLaunching();
+
+    let ctx = egui::Context::default();
+    let _menu = native_menu::NativeMenu::install(&ctx);
+
+    let bar = nsapp.mainMenu().expect("a main menu");
+    let tops: Vec<String> = (0..bar.numberOfItems()).filter_map(|i| bar.itemAtIndex(i)?.submenu()).map(|m| m.title().to_string()).collect();
+    assert_eq!(tops, ["GridCraft", "File", "Edit", "View", "Insert", "Format", "Tools", "Data", "Window", "Help"]);
+    assert_eq!(nsapp.windowsMenu().map(|m| m.title().to_string()).as_deref(), Some("Window"), "AppKit knows the Window menu");
+
+    println!("mac_menu_appkit: ok");
+}
+
+#[cfg(not(target_os = "macos"))]
+fn main() {}
diff --git a/crates/calc/src/eval.rs b/crates/calc/src/eval.rs
index 92a0a39..47a5119 100644
--- a/crates/calc/src/eval.rs
+++ b/crates/calc/src/eval.rs
@@ -88,6 +88,8 @@ pub struct Evaluator<'h> {
 
 struct FnCtx<'a, 'h> {
     ev: &'a mut Evaluator<'h>,
+    /// The criteria argument of a database function, when it is a reference.
+    criteria: Option<Area>,
 }
 
 impl Ctx for FnCtx<'_, '_> {
@@ -100,6 +102,28 @@ impl Ctx for FnCtx<'_, '_> {
     fn random(&mut self) -> f64 {
         self.ev.host.random()
     }
+    /// Excel's "formula as criteria": the formula is written for the first record, so its relative
+    /// references move down to `record`'s row, and the database's labels name its fields.
+    /// Known gap: the shifted references are not dependencies of the calling cell. One that lands
+    /// outside both the database and the criteria cell's own precedents (say `=G2<H2` with column H
+    /// outside the database) is read here but not tracked, so editing that cell doesn't recalculate
+    /// the D-function until something else does.
+    fn computed_criterion(&mut self, row: usize, col: usize, db: &Array, record: usize) -> Option<bool> {
+        let area = self.criteria?;
+        let at = area.range.start.offset(row as i64, col as i64).filter(|c| area.range.contains(*c))?;
+        let expr = self.ev.host.workbook().sheet(area.sheet)?.cell(at)?.formula.as_ref()?.expr_arc()?;
+        let shifted = gridcraft_formula::adjust::shift_relative((*expr).clone(), record as i64 - 1, 0);
+        let env = (0..db.cols)
+            .filter_map(|c| match db.get(0, c) {
+                Some(Value::Text(t)) if !t.trim().is_empty() => {
+                    Some((t.trim().to_string(), Ev::V(db.get(record, c).cloned().unwrap_or(Value::Empty))))
+                }
+                _ => None,
+            })
+            .collect();
+        let mut ev = Evaluator { host: &mut *self.ev.host, sheet: area.sheet, at, env, depth: self.ev.depth };
+        Some(matches!(ev.value(&shifted).scalar().to_bool(), Ok(true)))
+    }
 }
 
 impl<'h> Evaluator<'h> {
@@ -465,9 +489,22 @@ impl<'h> Evaluator<'h> {
                 }
             }
             _ => {
-                let x = self.value(a);
-                let y = self.value(b);
-                Ev::V(binary_values(op, &x, &y))
+                // A long chain such as A1+A2+…+A500 nests to the left: fold it in a loop instead
+                // of one level of recursion per operator (past the depth limit it was #CALC!).
+                let mut rest = vec![(op, b)];
+                let mut left = a;
+                while let Expr::Binary(o, l, r) = left
+                    && !matches!(o, BinOp::Range | BinOp::Union | BinOp::Intersect)
+                {
+                    rest.push((*o, r.as_ref()));
+                    left = l.as_ref();
+                }
+                let mut acc = self.value(left);
+                while let Some((o, r)) = rest.pop() {
+                    let y = self.value(r);
+                    acc = binary_values(o, &acc, &y);
+                }
+                Ev::V(acc)
             }
         }
     }
@@ -579,7 +616,7 @@ impl<'h> Evaluator<'h> {
                         let value = self.value(a);
                         evaluated.push(Arg { value, from_ref: false });
                     }
-                    let mut ctx = FnCtx { ev: self };
+                    let mut ctx = FnCtx { ev: self, criteria: None };
                     return gridcraft_functions::call(spec, &evaluated, &mut ctx).pipe(Ev::V);
                 }
                 let i = match index.to_number() {
@@ -737,6 +774,20 @@ impl<'h> Evaluator<'h> {
                 Ev::V(Value::Bool(r))
             }
             "MAP" | "REDUCE" | "SCAN" | "BYROW" | "BYCOL" | "MAKEARRAY" => self.higher_order(name, args),
+            "GROUPBY" | "PIVOTBY" => {
+                // The aggregation may be a function given by name (`SUM`): pass it as its name.
+                let i = if name == "GROUPBY" { 2 } else { 3 };
+                match args.get(i).and_then(|a| self.function_by_name(a)) {
+                    Some(f) => {
+                        let mut args = args.to_vec();
+                        if let Some(a) = args.get_mut(i) {
+                            *a = Expr::Text(f.into());
+                        }
+                        self.builtin(name, &args)
+                    }
+                    None => self.builtin(name, args),
+                }
+            }
             "NOW" | "TODAY" | "RAND" | "RANDBETWEEN" | "RANDARRAY" => {
                 self.host.note_volatile();
                 self.builtin(name, args)
@@ -762,8 +813,17 @@ impl<'h> Evaluator<'h> {
         let mut evaluated = Vec::with_capacity(args.len());
         // SUMIF/AVERAGEIF: the size of the criteria range (argument 1), which the sum range takes.
         let mut criteria_shape = None;
+        // Database functions: the criteria range (argument 2), whose formulas are computed criteria.
+        let mut criteria = None;
         for (i, a) in args.iter().enumerate() {
             let mut ev = self.eval(a);
+            if spec.category == gridcraft_functions::Category::Database
+                && i == 2
+                && let Ev::R(areas) = &ev
+                && let [area] = areas.as_slice()
+            {
+                criteria = Some(*area);
+            }
             if resizes_sum_range(name, args.len()) {
                 if i == 0 {
                     criteria_shape = ev_shape(&ev);
@@ -791,7 +851,7 @@ impl<'h> Evaluator<'h> {
             };
             evaluated.push(Arg { value, from_ref });
         }
-        let mut ctx = FnCtx { ev: self };
+        let mut ctx = FnCtx { ev: self, criteria };
         gridcraft_functions::call(spec, &evaluated, &mut ctx).pipe(Ev::V)
     }
 
@@ -845,13 +905,13 @@ impl<'h> Evaluator<'h> {
         };
         let args = [Arg { value, from_ref }];
         if kind != Agg::Count {
-            match gridcraft_functions::call(sum, &args, &mut FnCtx { ev: self }) {
+            match gridcraft_functions::call(sum, &args, &mut FnCtx { ev: self, criteria: None }) {
                 Value::Number(n) => acc.sum += n,
                 other => return Err(Ev::V(other)),
             }
         }
         if kind != Agg::Sum {
-            match gridcraft_functions::call(count, &args, &mut FnCtx { ev: self }) {
+            match gridcraft_functions::call(count, &args, &mut FnCtx { ev: self, criteria: None }) {
                 Value::Number(n) => acc.count = acc.count.saturating_add(n as u64),
                 other => return Err(Ev::V(other)),
             }
@@ -860,7 +920,12 @@ impl<'h> Evaluator<'h> {
     }
 
     pub fn apply_lambda(&mut self, l: &Lambda, args: &[Expr]) -> Ev {
-        if args.len() > l.params.len() {
+        // Too many or too few argument positions is #VALUE!. An explicitly empty position, as in
+        // `(1,)`, is `Expr::Missing` and still counts as a position (it binds as omitted). `f()`
+        // parses to no arguments, which for a one-parameter lambda can also be read as one empty
+        // position, so that call still binds the parameter as omitted.
+        let positions_ok = args.len() == l.params.len() || (args.is_empty() && l.params.len() == 1);
+        if !positions_ok {
             return err(CellError::Value);
         }
         let mut bound = Vec::with_capacity(l.params.len());
@@ -903,7 +968,26 @@ impl<'h> Evaluator<'h> {
         r
     }
 
-    fn lambda_arg(&mut self, e: Option<&Expr>) -> Option<Arc<Lambda>> {
+    /// A worksheet function given by name where a function is expected (`BYROW(A1:C3,SUM)`,
+    /// `GROUPBY(A2:A9,B2:B9,SUM)`): its name, unless a LET/LAMBDA variable or a defined name has
+    /// that name.
+    fn function_by_name(&self, e: &Expr) -> Option<String> {
+        let Expr::Name(n) = e else { return None };
+        if self.env.iter().any(|(k, _)| k.eq_ignore_ascii_case(n)) || self.host.workbook().name(n, self.sheet).is_some() {
+            return None;
+        }
+        let u = n.to_ascii_uppercase();
+        gridcraft_functions::lookup(&u).map(|_| u)
+    }
+
+    /// The function argument of a LAMBDA helper; a function given by name takes `arity`
+    /// arguments.
+    fn lambda_arg(&mut self, e: Option<&Expr>, arity: usize) -> Option<Arc<Lambda>> {
+        if let Some(f) = e.and_then(|x| self.function_by_name(x)) {
+            let params: Vec<String> = (0..arity).map(|i| format!("_xleta.{i}")).collect();
+            let body = Expr::Call(f, params.iter().map(|p| Expr::Name(p.clone())).collect());
+            return Some(Arc::new(Lambda { params, body, env: Vec::new() }));
+        }
         match e.map(|x| self.eval(x)) {
             Some(Ev::L(l)) => Some(l),
             _ => None,
@@ -922,7 +1006,7 @@ impl<'h> Evaluator<'h> {
                 if args.len() < 2 {
                     return err(CellError::Value);
                 }
-                let Some(l) = self.lambda_arg(args.last()) else { return err(CellError::Value) };
+                let Some(l) = self.lambda_arg(args.last(), args.len() - 1) else { return err(CellError::Value) };
                 let arrays: Vec<Arc<Array>> = args[..args.len() - 1].iter().map(|a| as_array(self.value(a))).collect();
                 let rows = arrays.iter().map(|a| a.rows).max().unwrap_or(1);
                 let cols = arrays.iter().map(|a| a.cols).max().unwrap_or(1);
@@ -945,7 +1029,7 @@ impl<'h> Evaluator<'h> {
                 }
                 let mut acc = self.value(&args[0]);
                 let arr = as_array(self.value(&args[1]));
-                let Some(l) = self.lambda_arg(args.get(2)) else { return err(CellError::Value) };
+                let Some(l) = self.lambda_arg(args.get(2), 2) else { return err(CellError::Value) };
                 if l.params.len() != 2 {
                     return err(CellError::Value);
                 }
@@ -969,7 +1053,7 @@ impl<'h> Evaluator<'h> {
                     return err(CellError::Value);
                 }
                 let arr = as_array(self.value(&args[0]));
-                let Some(l) = self.lambda_arg(args.get(1)) else { return err(CellError::Value) };
+                let Some(l) = self.lambda_arg(args.get(1), 1) else { return err(CellError::Value) };
                 let Some(p) = l.params.first().cloned() else { return err(CellError::Value) };
                 let by_row = name == "BYROW";
                 let n = if by_row { arr.rows } else { arr.cols };
@@ -998,7 +1082,7 @@ impl<'h> Evaluator<'h> {
                 if rows < 1.0 || cols < 1.0 || rows * cols > MAX_CELLS as f64 {
                     return err(CellError::Value);
                 }
-                let Some(l) = self.lambda_arg(args.get(2)) else { return err(CellError::Value) };
+                let Some(l) = self.lambda_arg(args.get(2), 2) else { return err(CellError::Value) };
                 if l.params.len() != 2 {
                     return err(CellError::Value);
                 }
@@ -1054,10 +1138,10 @@ impl<'h> Evaluator<'h> {
         if h == 0 || w == 0 {
             return err(CellError::Ref);
         }
-        let r0 = base.range.start.row as i64 + rows;
-        let c0 = base.range.start.col as i64 + cols;
-        let (r0, r1) = if h > 0 { (r0, r0 + h - 1) } else { (r0 + h + 1, r0) };
-        let (c0, c1) = if w > 0 { (c0, c0 + w - 1) } else { (c0 + w + 1, c0) };
+        let r0 = (base.range.start.row as i64).saturating_add(rows);
+        let c0 = (base.range.start.col as i64).saturating_add(cols);
+        let (r0, r1) = if h > 0 { (r0, r0.saturating_add(h - 1)) } else { (r0.saturating_add(h + 1), r0) };
+        let (c0, c1) = if w > 0 { (c0, c0.saturating_add(w - 1)) } else { (c0.saturating_add(w + 1), c0) };
         if r0 < 0 || c0 < 0 || r1 >= MAX_ROWS as i64 || c1 >= MAX_COLS as i64 {
             return err(CellError::Ref);
         }
@@ -1081,7 +1165,15 @@ impl<'h> Evaluator<'h> {
                 v.scalar().to_bool().unwrap_or(true)
             }
         };
-        let text = if a1 { text } else { r1c1_to_a1(&text, self.at).unwrap_or(text) };
+        let text = if a1 {
+            text
+        } else {
+            match r1c1_to_a1(&text, self.at) {
+                Ok(Some(a1_text)) => a1_text,
+                Ok(None) => text,
+                Err(e) => return err(e),
+            }
+        };
         match gridcraft_formula::parse(&text) {
             Ok(e @ (Expr::Ref(_) | Expr::Name(_) | Expr::Struct(_))) => match self.eval(&e) {
                 r @ Ev::R(_) => r,
@@ -1152,7 +1244,8 @@ impl<'h> Evaluator<'h> {
         }
         match src {
             Ev::R(areas) => {
-                let Some(a) = areas.get((area_n - 1).max(0) as usize).copied() else { return err(CellError::Ref) };
+                let area = usize::try_from((area_n as u64).saturating_sub(1)).ok();
+                let Some(a) = area.and_then(|i| areas.get(i)).copied() else { return err(CellError::Ref) };
                 let r = a.range;
                 // A single row or column with one index picks along it.
                 let (row, col) = if two_args && r.height() == 1 { (1, row) } else { (row, col) };
@@ -1221,7 +1314,7 @@ impl<'h> Evaluator<'h> {
                         }
                     }
                 }
-                let mut ctx = FnCtx { ev: self };
+                let mut ctx = FnCtx { ev: self, criteria: None };
                 return match gridcraft_functions::call(spec, &xargs, &mut ctx) {
                     Value::Number(p) if p >= 1.0 => {
                         let k = p as u32 - 1;
@@ -1275,7 +1368,7 @@ impl<'h> Evaluator<'h> {
                     _ => "v",
                 }))
             }
-            "width" => Ev::V(Value::number(sheet.map_or(8.43, |s| (s.col_width(c.col) as f64 / 7.0 * 100.0).round() / 100.0).round())),
+            "width" => Ev::V(Value::number(sheet.map_or(8.43, |s| gridcraft_model::points_to_chars(s.col_width(c.col) as f64)).round())),
             "filename" => Ev::V(Value::text(String::new())),
             "sheetname" => Ev::V(Value::text(sheet.map(|s| s.name.clone()).unwrap_or_default())),
             "protect" => Ev::V(Value::number(if sheet.is_some_and(|s| wb.styles.get(s.style_id(c)).protection.locked) { 1.0 } else { 0.0 })),
@@ -1290,7 +1383,9 @@ impl<'h> Evaluator<'h> {
     }
 
     fn subtotal(&mut self, name: &str, args: &[Expr]) -> Ev {
-        if args.len() < 2 {
+        // SUBTOTAL needs function_num and ref1; AGGREGATE needs function_num, options and ref1.
+        let min_args = if name == "AGGREGATE" { 3 } else { 2 };
+        if args.len() < min_args {
             return err(CellError::Value);
         }
         let code = match self.arg_num(args, 0, 0.0) {
@@ -1315,7 +1410,8 @@ impl<'h> Evaluator<'h> {
         // SUBTOTAL documentation); 101-111 also leave out rows hidden by hand.
         let skip_filtered = name == "SUBTOTAL";
         let skip_errors = matches!(options, 2 | 3 | 6 | 7);
-        let skip_nested = options <= 3;
+        // SUBTOTAL always leaves out nested SUBTOTAL/AGGREGATE cells (101-111 too); AGGREGATE does so for options 0-3.
+        let skip_nested = name == "SUBTOTAL" || options <= 3;
         let mut values = Vec::new();
         let mut k = None;
         let refs = if name == "AGGREGATE" && func >= 14 { &rest[..1.min(rest.len())] } else { rest };
@@ -1406,37 +1502,42 @@ fn same_kind(a: &Value, b: &Value) -> bool {
     std::mem::discriminant(a) == std::mem::discriminant(b) || (a.is_empty() || b.is_empty())
 }
 
-/// Converts an R1C1 reference text to A1 (for INDIRECT(…, FALSE)).
-pub fn r1c1_to_a1(s: &str, at: CellRef) -> Option<String> {
+/// Converts an R1C1 reference text to A1 (for INDIRECT(…, FALSE)). `Ok(None)` means the text is
+/// not R1C1; `Err` means it is R1C1 but points past the sheet.
+pub fn r1c1_to_a1(s: &str, at: CellRef) -> Result<Option<String>, CellError> {
     let (sheet, body) = match s.rsplit_once('!') {
         Some((sh, b)) => (format!("{sh}!"), b),
         None => (String::new(), s),
     };
-    let conv = |part: &str| -> Option<String> {
+    let conv = |part: &str| -> Result<Option<String>, CellError> {
         let u = part.to_ascii_uppercase();
-        let rest = u.strip_prefix('R')?;
-        let (rpart, cpart) = rest.split_once('C')?;
-        let num = |p: &str, base: u32| -> Option<(u32, bool)> {
-            if p.is_empty() {
-                return Some((base, false));
-            }
-            if let Some(inner) = p.strip_prefix('[').and_then(|x| x.strip_suffix(']')) {
-                let d: i64 = inner.parse().ok()?;
-                let v = base as i64 + d;
-                return if v >= 0 { Some((v as u32, false)) } else { None };
-            }
-            let v: u32 = p.parse().ok()?;
-            Some((v.checked_sub(1)?, true))
+        let Some((rpart, cpart)) = u.strip_prefix('R').and_then(|rest| rest.split_once('C')) else { return Ok(None) };
+        // `None`: not R1C1. `Some(None)`: R1C1, but past the sheet.
+        let num = |p: &str, base: u32, max: u32| -> Option<Option<(u32, bool)>> {
+            let (v, absolute) = if p.is_empty() {
+                (Some(i64::from(base)), false)
+            } else if let Some(inner) = p.strip_prefix('[').and_then(|x| x.strip_suffix(']')) {
+                (i64::from(base).checked_add(inner.parse().ok()?), false)
+            } else {
+                (p.parse::<u32>().ok()?.checked_sub(1).map(i64::from), true)
+            };
+            Some(v.filter(|v| (0..i64::from(max)).contains(v)).map(|v| (v as u32, absolute)))
         };
-        let (r, ra) = num(rpart, at.row)?;
-        let (c, ca) = num(cpart, at.col)?;
-        Some(format!("{}{}{}{}", if ca { "$" } else { "" }, gridcraft_core::col_to_letters(c), if ra { "$" } else { "" }, r + 1))
+        let (Some(r), Some(c)) = (num(rpart, at.row, MAX_ROWS), num(cpart, at.col, MAX_COLS)) else { return Ok(None) };
+        let (Some((r, ra)), Some((c, ca))) = (r, c) else { return Err(CellError::Ref) };
+        Ok(Some(format!("{}{}{}{}", if ca { "$" } else { "" }, gridcraft_core::col_to_letters(c), if ra { "$" } else { "" }, r + 1)))
     };
     let out = match body.split_once(':') {
-        Some((a, b)) => format!("{}:{}", conv(a)?, conv(b)?),
-        None => conv(body)?,
+        Some((a, b)) => match (conv(a)?, conv(b)?) {
+            (Some(a), Some(b)) => format!("{a}:{b}"),
+            _ => return Ok(None),
+        },
+        None => match conv(body)? {
+            Some(x) => x,
+            None => return Ok(None),
+        },
     };
-    Some(format!("{sheet}{out}"))
+    Ok(Some(format!("{sheet}{out}")))
 }
 
 /// The aggregates that can fold a reference without building an array.
diff --git a/crates/calc/src/recalc.rs b/crates/calc/src/recalc.rs
index 553e764..b391821 100644
--- a/crates/calc/src/recalc.rs
+++ b/crates/calc/src/recalc.rs
@@ -898,11 +898,11 @@ impl Calc {
         // Spill areas of changed anchors also change.
         for &k in changed {
             if let Some(r) = wb.sheet(k.0).and_then(|s| s.spill_ranges.get(&k.1)) {
-                seeds.extend(r.iter().take(65536).map(|c| (k.0, c)));
+                seeds.extend(r.iter().map(|c| (k.0, c)));
             }
         }
         for (si, r) in &cleared {
-            seeds.extend(r.iter().take(65536).map(|c| (*si, c)));
+            seeds.extend(r.iter().map(|c| (*si, c)));
         }
         let t0 = prof_now();
         let dirty = self.dirty_closure(wb, &seeds);
diff --git a/crates/calc/src/tests.rs b/crates/calc/src/tests.rs
index 5133409..8b29f63 100644
--- a/crates/calc/src/tests.rs
+++ b/crates/calc/src/tests.rs
@@ -157,6 +157,21 @@ fn index_with_arrays_of_positions() {
     assert_eq!(t.num("E7"), 6.0);
 }
 
+#[test]
+fn index_area_number_overflow() {
+    let mut t = T::new();
+    t.set("A1", "7");
+    t.set("D1", "9");
+    for (area, expected) in [("1", 7.0), ("2", 9.0)] {
+        t.set("G5", &format!("=INDEX((A1:B2,D1:E2),1,1,{area})"));
+        assert_eq!(t.num("G5"), expected, "area {area}");
+    }
+    for area in ["3", "1E300", "-1", "-1E300"] {
+        t.set("G5", &format!("=INDEX((A1:B2,D1:E2),1,1,{area})"));
+        assert_eq!(t.get("G5"), Value::Error(CellError::Ref), "area {area}");
+    }
+}
+
 #[test]
 fn errors_and_cycles() {
     let mut t = T::new();
@@ -167,6 +182,11 @@ fn errors_and_cycles() {
     assert!(t.get("B1").is_error());
     t.set("C1", "=NOSUCHFN(1)");
     assert_eq!(t.get("C1"), Value::Error(CellError::Name));
+    // `_xludf.` marks a user-defined function, never the built-in of the same name (#726).
+    for f in ["=_xludf.CONCAT(\"a\",\"b\")", "=_xludf.SUM(1,2)", "=_xludf.EOMONTH()"] {
+        t.set("C3", f);
+        assert_eq!(t.get("C3"), Value::Error(CellError::Name), "{f}");
+    }
     t.set("C2", "=1+");
     assert_eq!(t.get("C2"), Value::Error(CellError::Name));
 }
@@ -412,6 +432,37 @@ fn references_functions() {
     assert_eq!(t.num("B6"), 105.0);
 }
 
+#[test]
+fn indirect_r1c1_out_of_bounds() {
+    for reference in ["R[9223372036854775807]C", "RC[9223372036854775807]", "R[4294967296]C", "R[4294967291]C", "R[2000000]C", "RC[20000]"] {
+        let mut t = T::new();
+        t.set("D5", &format!("=ROW(INDIRECT(\"{reference}\",FALSE))"));
+        assert_eq!(t.get("D5"), Value::Error(CellError::Ref), "{reference}");
+    }
+}
+
+#[test]
+fn indirect_r1c1_past_the_sheet_does_not_fall_back_to_a1() {
+    let mut t = T::new();
+    t.set("RC16385", "78");
+    for reference in ["RC16385", "rc16385", "RC1:RC16385"] {
+        t.set("D5", &format!("=INDIRECT(\"{reference}\",FALSE)"));
+        assert_eq!(t.get("D5"), Value::Error(CellError::Ref), "{reference}");
+    }
+}
+
+#[test]
+fn indirect_r1c1_valid_references() {
+    let mut t = T::new();
+    t.set("E6", "11");
+    t.set("A1", "22");
+    t.set("D4", "33");
+    for (reference, expected) in [("R[1]C[1]", 11.0), ("R1C1", 22.0), ("R[-1]C", 33.0)] {
+        t.set("D5", &format!("=INDIRECT(\"{reference}\",FALSE)"));
+        assert_eq!(t.num("D5"), expected, "{reference}");
+    }
+}
+
 #[test]
 fn relative_names() {
     let mut t = T::new();
@@ -501,6 +552,56 @@ fn let_lambda() {
     assert_eq!(t.num("A4"), 14.0);
 }
 
+#[test]
+fn functions_given_by_name() {
+    let mut t = T::new();
+    for (i, (k, v)) in [("a", 1), ("b", -2), ("a", 3)].iter().enumerate() {
+        t.set(&format!("A{}", i + 1), k);
+        t.set(&format!("B{}", i + 1), &v.to_string());
+    }
+    t.set("D1", "=BYROW(B1:B3,SUM)");
+    assert_eq!(t.num("D2"), -2.0);
+    t.set("E1", "=MAP(B1:B3,ABS)");
+    assert_eq!(t.num("E2"), 2.0);
+    t.set("F1", "=REDUCE(0,B1:B3,SUM)");
+    assert_eq!(t.num("F1"), 2.0);
+    t.set("G1", "=GROUPBY(A1:A3,B1:B3,SUM,0,0)");
+    assert_eq!(t.get("G1"), Value::from("a"));
+    assert_eq!(t.num("H1"), 4.0);
+    // A LET variable of that name is still the variable.
+    t.set("J1", "=LET(ABS,LAMBDA(x,x*10),SUM(MAP(B1:B3,ABS)))");
+    assert_eq!(t.num("J1"), 20.0);
+fn lambda_argument_count() {
+    let mut t = T::new();
+    t.wb.names.push(gridcraft_model::DefinedName {
+        name: "AddPair".into(),
+        scope: None,
+        formula: "LAMBDA(a,b,a+b)".into(),
+        comment: String::new(),
+        hidden: false,
+    });
+    t.calc.rebuild(&t.wb);
+    let omit = "LAMBDA(x,y,IF(ISOMITTED(y),\"Missing\",x+y))";
+    t.set("A1", "=LAMBDA(a,b,a+b)(2)");
+    t.set("A2", "=LAMBDA(a,b,a+b)(2,3,4)");
+    t.set("A3", &format!("={omit}(1,)"));
+    t.set("A4", &format!("={omit}(1)"));
+    t.set("A5", &format!("={omit}(1,2)"));
+    t.set("A6", "=LAMBDA(7)()");
+    t.set("A7", "=AddPair(2)");
+    t.set("A8", "=AddPair(2,3)");
+    assert_eq!(t.get("A1"), Value::Error(CellError::Value));
+    assert_eq!(t.get("A2"), Value::Error(CellError::Value));
+    assert_eq!(t.get("A3"), Value::Text("Missing".into()));
+    assert_eq!(t.get("A4"), Value::Error(CellError::Value));
+    assert_eq!(t.num("A5"), 3.0);
+    assert_eq!(t.num("A6"), 7.0);
+    assert_eq!(t.get("A7"), Value::Error(CellError::Value));
+    assert_eq!(t.num("A8"), 5.0);
+    t.set("A9", "=LAMBDA(x,ISOMITTED(x))()");
+    assert_eq!(t.get("A9"), Value::Bool(true));
+}
+
 #[test]
 fn names_and_sheets() {
     let mut t = T::new();
@@ -549,6 +650,17 @@ fn text_function() {
     assert_eq!(t.get("A1"), Value::from("1,234.50"));
 }
 
+#[test]
+fn long_operator_chains() {
+    let mut t = T::new();
+    t.set("A1", "1");
+    // 1,000 additions: a formula of 3,000 characters, well within Excel's 8,192.
+    t.set("B1", &format!("={}", vec!["A1"; 1000].join("+")));
+    assert_eq!(t.num("B1"), 1000.0);
+    t.set("B2", &format!("=5{}", "+1-1".repeat(600)));
+    assert_eq!(t.num("B2"), 5.0);
+}
+
 #[test]
 fn subtotal_skips_hidden() {
     let mut t = T::new();
@@ -562,6 +674,29 @@ fn subtotal_skips_hidden() {
     assert_eq!(t.num("B2"), 6.0);
 }
 
+#[test]
+fn subtotal_109_skips_nested_subtotal() {
+    let mut t = T::new();
+    t.set("A1", "2");
+    t.set("A2", "=SUBTOTAL(9,A1)");
+    t.set("C1", "=SUBTOTAL(109,A1:A2)");
+    t.set("C2", "=SUBTOTAL(9,A1:A2)");
+    t.set("C3", "=SUBTOTAL(109,A1)");
+    assert_eq!(t.num("C1"), 2.0);
+    assert_eq!(t.num("C2"), 2.0);
+    assert_eq!(t.num("C3"), 2.0);
+    // Manually hidden rows are still left out by 109 only.
+    let mut t = T::new();
+    t.set("A1", "1");
+    t.set("A2", "2");
+    t.set("A3", "=SUBTOTAL(9,A1:A2)");
+    t.wb.sheet_mut(0).unwrap().rows.insert(1, gridcraft_model::LineInfo { hidden: true, ..Default::default() });
+    t.set("B1", "=SUBTOTAL(109,A1:A3)");
+    t.set("B2", "=SUBTOTAL(9,A1:A3)");
+    assert_eq!(t.num("B1"), 1.0);
+    assert_eq!(t.num("B2"), 3.0);
+}
+
 /// SUBTOTAL leaves out rows a filter hides for every function number, while 1-11 keep rows
 /// hidden by hand (as in ConditionalFormattingSamples.xlsx, where `SUBTOTAL(9,Table69[Sales])`
 /// under a filtered table adds only the visible rows).
@@ -608,6 +743,23 @@ fn subtotal_skips_filtered_rows() {
     }
 }
 
+#[test]
+fn aggregate_without_data_argument_is_an_error() {
+    let mut t = T::new();
+    t.set("A1", "1");
+    t.set("A2", "2");
+    t.set("D1", "=AGGREGATE(9,0)");
+    t.set("D2", "=AGGREGATE(4,0)");
+    t.set("D3", "=AGGREGATE(9,0,A1:A2)");
+    t.set("D4", "=AGGREGATE(9,0,A3:A4)");
+    t.set("D5", "=AGGREGATE(9,0,A1:A2,A1:A2)");
+    assert_eq!(t.get("D1"), Value::Error(CellError::Value));
+    assert_eq!(t.get("D2"), Value::Error(CellError::Value));
+    assert_eq!(t.num("D3"), 3.0);
+    assert_eq!(t.num("D4"), 0.0);
+    assert_eq!(t.num("D5"), 6.0);
+}
+
 #[test]
 fn recalc_all_after_load() {
     let mut t = T::new();
@@ -968,3 +1120,95 @@ fn trim_references() {
     t.set("K20", "=SUM(Q1:.Q9)");
     assert_eq!(t.get("K20"), Value::Error(CellError::Calc));
 }
+
+#[test]
+fn cell_width_is_the_column_width_dialog_value_rounded() {
+    // #735: Excel 365 values. Widths in px as `home.columnWidth {"chars"}` sets them
+    // (chars * 7 + 5): 10.71 -> 80, 12 -> 89, 10.57 -> 79, 2.86 -> 25; B keeps the default 8.43 (64).
+    let mut t = T::new();
+    let sh = t.wb.sheet_mut(0).unwrap();
+    for (col, px) in [(2, 80.0), (3, 89.0), (4, 79.0), (5, 25.0)] {
+        sh.cols.insert(col, gridcraft_model::LineInfo { size: Some(px), ..Default::default() });
+    }
+    for (at, col) in [("H1", "B"), ("H2", "C"), ("H3", "D"), ("H4", "E"), ("H5", "F")] {
+        t.set(at, &format!("=CELL(\"width\",{col}1)"));
+    }
+    assert_eq!([t.num("H1"), t.num("H2"), t.num("H3"), t.num("H4"), t.num("H5")], [8.0, 11.0, 12.0, 11.0, 3.0]);
+/// Expected results are Excel's, from Apache POI's `DGet.xls` (rows 46-49): a criteria cell holding
+/// a formula under a label that names no field is evaluated for every record.
+#[test]
+fn database_functions_with_computed_criteria() {
+    let mut t = T::new();
+    let db = [
+        ["name", "age", "size", "headgear", "glasses"],
+        ["Huey", "6", "45", "cap~", "FALSE"],
+        ["Dewey", "7", "fourty-six", "cap?", "FALSE"],
+        ["Louie", "8", "47", "cap*", "FALSE"],
+        ["Donald", "32", "70", "sailor's hat", "FALSE"],
+        ["Scrooge", "62", "65", "top hat", "TRUE"],
+    ];
+    for (r, row) in db.iter().enumerate() {
+        for (c, v) in row.iter().enumerate() {
+            t.set(&format!("{}{}", ["F", "G", "H", "I", "J"][c], r + 2), v);
+        }
+    }
+    t.set("G45", "7");
+    let cases = [
+        // Relative references are to the first record's row and move to each record's row;
+        // `$G$45` stays put.
+        ("G", "=G2<$G$45", "Dewey"),
+        // Column labels stand for the record's fields.
+        ("H", "=glasses=TRUE", "Scrooge"),
+        ("I", "=age<7", "Huey"),
+        ("J", "=size/7=10", "Donald"),
+        // An absolute reference to a cell that is not the first record's.
+        ("K", "=H3=$L$1", "Donald"),
+    ];
+    t.set("L1", "70");
+    for (i, (col, formula, _)) in cases.iter().enumerate() {
+        t.set(&format!("{col}46"), "Formula");
+        t.set(&format!("{col}47"), formula);
+        t.set(&format!("B{}", 46 + i), &format!("=DGET($F$2:$J$7,\"name\",{col}46:{col}47)"));
+    }
+    for (i, (_, formula, want)) in cases.iter().enumerate() {
+        assert_eq!(t.get(&format!("B{}", 46 + i)), Value::text(*want), "{formula}");
+    }
+    // Every database function takes them, ANDed with the other criteria of their row.
+    // Text sorts after numbers, so Dewey's "fourty-six" is > 40.
+    t.set("L47", "=size>40");
+    t.set("M46", "age");
+    t.set("M47", ">6");
+    t.set("B51", "=DCOUNT($F$2:$J$7,\"age\",I46:I47)");
+    t.set("B52", "=DSUM($F$2:$J$7,\"age\",G46:G47)");
+    t.set("B53", "=DCOUNTA($F$2:$J$7,\"name\",L46:M47)");
+    assert_eq!(t.num("B51"), 1.0);
+    assert_eq!(t.num("B52"), 7.0);
+    assert_eq!(t.num("B53"), 4.0);
+#[test]
+fn offset_extreme_arguments_return_ref() {
+    let wb = Workbook::new();
+    for formula in [
+        "=OFFSET(B2,1E300,0)",
+        "=OFFSET(B2,0,1E300)",
+        "=OFFSET(B2,0,0,1E300,1)",
+        "=OFFSET(B2,0,0,1,1E300)",
+        "=OFFSET(B2,-1E300,0)",
+        "=OFFSET(B2,0,-1E300)",
+        "=OFFSET(B2,0,0,-1E300,1)",
+        "=OFFSET(B2,0,0,1,-1E300)",
+        "=OFFSET(B2,1E300,0,-1E300,1)",
+        "=OFFSET(B2,0,1E300,1,-1E300)",
+        "=OFFSET(B2,-1E300,0,-1E300,1)",
+    ] {
+        assert_eq!(crate::evaluate(&wb, 0, c("D1"), formula), Value::Error(CellError::Ref), "{formula}");
+    }
+    for (formula, expected) in [
+        ("=ROW(OFFSET(B2,1.9,0))", 3.0),
+        ("=COLUMN(OFFSET(B2,0,-1.9))", 1.0),
+        ("=ROWS(OFFSET(B2,0,0,-2,1))", 2.0),
+        ("=COLUMNS(OFFSET(B2,0,0,1,-2))", 2.0),
+        ("=ROWS(OFFSET(A1,0,0,1048576,1))", 1048576.0),
+    ] {
+        assert_eq!(crate::evaluate(&wb, 0, c("D1"), formula), Value::Number(expected), "{formula}");
+    }
+}
diff --git a/crates/chart/src/axis.rs b/crates/chart/src/axis.rs
index eb4f733..8686bf7 100644
--- a/crates/chart/src/axis.rs
+++ b/crates/chart/src/axis.rs
@@ -122,7 +122,7 @@ impl Fmt {
     pub fn new(code: &str) -> Fmt {
         let t = code.trim();
         let general = t.is_empty() || t.eq_ignore_ascii_case("general");
-        Fmt { general, fmt: NumberFormat::parse(if general { "General" } else { t }) }
+        Fmt { general, fmt: NumberFormat::parse_cached(if general { "General" } else { t }) }
     }
     /// Formats `v`; `step` (axis labels) fixes the decimals for General.
     pub fn format(&self, v: f64, step: Option<f64>) -> String {
diff --git a/crates/chart/src/lib.rs b/crates/chart/src/lib.rs
index 083ff8b..697e2a7 100644
--- a/crates/chart/src/lib.rs
+++ b/crates/chart/src/lib.rs
@@ -124,6 +124,9 @@ impl Measure for ApproxMeasure {
 pub struct ChartData {
     pub categories: Vec<String>,
     pub series: Vec<SeriesData>,
+    /// Workbook-theme colours for the points of pie-like charts, repeating (point `j` uses entry `j % len`); empty uses the default theme.
+    #[serde(default)]
+    pub palette: Vec<Rgba>,
 }
 
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
diff --git a/crates/chart/src/raster.rs b/crates/chart/src/raster.rs
index 5da9d35..67ed53e 100644
--- a/crates/chart/src/raster.rs
+++ b/crates/chart/src/raster.rs
@@ -138,7 +138,8 @@ fn circle(cx: f32, cy: f32, r: f32) -> Vec<[f32; 2]> {
 }
 
 fn rounded_rect(x: f32, y: f32, w: f32, h: f32, r: f32) -> Vec<[f32; 2]> {
-    let r = r.clamp(0.0, w.min(h) / 2.0);
+    // A negative or NaN extent gives an upper bound of 0 (clamp panics if max < min or NaN).
+    let r = r.clamp(0.0, (w.min(h) / 2.0).max(0.0));
     if r < 0.5 {
         return vec![[x, y], [x + w, y], [x + w, y + h], [x, y + h]];
     }
diff --git a/crates/chart/src/render.rs b/crates/chart/src/render.rs
index 63d30d9..037b909 100644
--- a/crates/chart/src/render.rs
+++ b/crates/chart/src/render.rs
@@ -129,7 +129,7 @@ fn plot_kind(chart: &Chart, s: &SeriesData) -> ChartKind {
 fn point_color(data: &ChartData, j: usize) -> Rgba {
     match (j, data.series.first()) {
         (0, Some(s)) => s.color,
-        _ => series_color(&Theme::default(), j),
+        _ => j.checked_rem(data.palette.len()).and_then(|k| data.palette.get(k)).copied().unwrap_or_else(|| series_color(&Theme::default(), j)),
     }
 }
 
@@ -190,6 +190,7 @@ fn sanitize_vals(v: &[Option<f64>]) -> Vec<Option<f64>> {
 
 fn sanitize(d: &ChartData) -> ChartData {
     ChartData {
+        palette: d.palette.iter().take(MAX_POINTS).copied().collect(),
         categories: d.categories.iter().take(MAX_POINTS).cloned().collect(),
         series: d
             .series
@@ -254,7 +255,7 @@ fn draw_kind(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
         Doughnut => pie(ctx, chart, data, area, 0.5, false),
         Sunburst => pie(ctx, chart, data, area, 0.2, true),
         Treemap => treemap(ctx, chart, data, area),
-        Funnel => funnel(ctx, data, area),
+        Funnel => funnel(ctx, chart, data, area),
         Radar => radar(ctx, chart, data, area),
         _ => {
             let area = axis_titles(ctx, chart, area);
@@ -266,8 +267,8 @@ fn draw_kind(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
                 Scatter | ScatterLines | Bubble => scatter(ctx, chart, data, area),
                 Histogram => histogram(ctx, chart, data, area),
                 Waterfall => waterfall(ctx, chart, data, area),
-                BoxWhisker => box_whisker(ctx, data, area),
-                Stock => stock(ctx, data, area),
+                BoxWhisker => box_whisker(ctx, chart, data, area),
+                Stock => stock(ctx, chart, data, area),
                 _ => cartesian(ctx, chart, data, area, false),
             }
         }
@@ -970,6 +971,8 @@ fn cartesian(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx, horizonta
     let nslots = slot_keys.len().max(1) as f32;
     let bw = cw / (nslots + 1.5);
     let labels_on = chart.data_labels && ncat <= MAX_LABELS;
+    // Area labels wait until every area is filled, so a later (stacked) area can't paint over them.
+    let mut area_labels = Vec::new();
 
     // Areas first, then columns, then lines on top.
     for pass in 0..3 {
@@ -998,6 +1001,13 @@ fn cartesian(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx, horizonta
                         let c = center(j);
                         top.push([c, vpos(t, &sc)]);
                         base.push([c, vpos(b, &sc)]);
+                        // Source values (not stack totals), just above the top edge like the line labels.
+                        if labels_on
+                            && sp.is_some()
+                            && let Some(v) = s.values.get(j).copied().flatten()
+                        {
+                            area_labels.push((c, vpos(t, &sc) - 5.0, fmt.format(v, None)));
+                        }
                     }
                     if top.len() == 1 {
                         // A single point: give it some width.
@@ -1072,6 +1082,9 @@ fn cartesian(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx, horizonta
                 }
             }
         }
+        for (x, y, t) in area_labels.drain(..) {
+            ctx.text(x, y, &t, LABEL_SIZE, TEXT, HAlign::Center, VAlign::Bottom);
+        }
     }
     // Trendlines on top: x is the category number 1..n.
     let mut trend_labels = Vec::new();
@@ -1201,10 +1214,12 @@ fn histogram(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
         bins = 1;
     }
     let width = if bins == 1 && span.partial_cmp(&0.0) != Some(std::cmp::Ordering::Greater) { 1.0 } else { span / bins as f64 };
+    // Upper edge of each bin, exactly as shown in the labels below. Bins are right-inclusive (the first is closed on both sides), so a value
+    // equal to an edge belongs to the bin that ends there.
+    let edges: Vec<f64> = (0..bins).map(|b| if b + 1 == bins { hi.max(lo + b as f64 * width) } else { lo + (b + 1) as f64 * width }).collect();
     let mut counts = vec![0usize; bins];
     for v in &vals {
-        let b = if width > 0.0 { ((v - lo) / width).floor() } else { 0.0 };
-        let b = if b.is_finite() && b > 0.0 { (b as usize).min(bins - 1) } else { 0 };
+        let b = edges.partition_point(|e| e < v).min(bins - 1);
         if let Some(c) = counts.get_mut(b) {
             *c += 1;
         }
@@ -1213,7 +1228,7 @@ fn histogram(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
     let labels: Vec<String> = (0..bins)
         .map(|b| {
             let a = lo + b as f64 * width;
-            let e = if b + 1 == bins { hi.max(a) } else { a + width };
+            let e = edges.get(b).copied().unwrap_or(a);
             let open = if b == 0 { '[' } else { '(' };
             format!("{open}{}, {}]", f.format(a, Some(width / 10.0)), f.format(e, Some(width / 10.0)))
         })
@@ -1301,7 +1316,7 @@ fn waterfall(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
 
 // ---------------------------------------------------------------- funnel
 
-fn funnel(ctx: &mut Ctx, data: &ChartData, area: Bx) {
+fn funnel(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
     let Some(s) = data.series.first() else { return };
     let n = data.categories.len().max(s.values.len()).min(MAX_CATS);
     if n == 0 {
@@ -1331,9 +1346,11 @@ fn funnel(ctx: &mut Ctx, data: &ChartData, area: Bx) {
         }
         if show {
             let yc = y + bh / 2.0;
-            let t = f.format(s.values.get(j).copied().flatten().unwrap_or(0.0), None);
-            let color = if ctx.tw(&t, LABEL_SIZE) + 4.0 <= bw { on(s.color) } else { TEXT };
-            ctx.text(plot.cx(), yc, &t, LABEL_SIZE, color, HAlign::Center, VAlign::Middle);
+            if chart.data_labels {
+                let t = f.format(s.values.get(j).copied().flatten().unwrap_or(0.0), None);
+                let color = if ctx.tw(&t, LABEL_SIZE) + 4.0 <= bw { on(s.color) } else { TEXT };
+                ctx.text(plot.cx(), yc, &t, LABEL_SIZE, color, HAlign::Center, VAlign::Middle);
+            }
             let l = ctx.fit(labels.get(j).map(String::as_str).unwrap_or(""), LABEL_SIZE, lw - 8.0);
             ctx.text(plot.x - 6.0, yc, &l, LABEL_SIZE, TEXT, HAlign::Right, VAlign::Middle);
         }
@@ -1557,12 +1574,12 @@ fn quantile(sorted: &[f64], q: f64) -> f64 {
     a + (b - a) * frac
 }
 
-fn box_whisker(ctx: &mut Ctx, data: &ChartData, area: Bx) {
+fn box_whisker(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
     let labels: Vec<String> = data.series.iter().map(|s| s.name.clone()).collect();
     let Some((lo, hi)) = value_range(data.series.iter().flat_map(|s| s.values.iter().flatten().copied())) else { return };
     let ys = nice_scale(lo, hi, false);
     let f = Fmt::new(data.series.first().map(|s| s.number_format.as_str()).unwrap_or("General"));
-    let plot = frame(ctx, area, CatAxis::Labels(&labels), &ValAxis { scale: ys, fmt: &f }, None, false, true);
+    let plot = frame(ctx, area, CatAxis::Labels(&labels), &ValAxis { scale: ys, fmt: &f }, None, false, chart.gridlines);
     if !plot.ok() {
         return;
     }
@@ -1601,7 +1618,7 @@ fn box_whisker(ctx: &mut Ctx, data: &ChartData, area: Bx) {
 
 // ---------------------------------------------------------------- stock
 
-fn stock(ctx: &mut Ctx, data: &ChartData, area: Bx) {
+fn stock(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx) {
     let ncat = data.categories.len().max(data.series.iter().map(|s| s.values.len()).max().unwrap_or(0)).min(MAX_CATS);
     if ncat == 0 {
         return;
@@ -1610,7 +1627,7 @@ fn stock(ctx: &mut Ctx, data: &ChartData, area: Bx) {
     let Some((lo, hi)) = value_range(data.series.iter().flat_map(|s| s.values.iter().flatten().copied())) else { return };
     let ys = nice_scale(lo, hi, false);
     let f = Fmt::new(data.series.first().map(|s| s.number_format.as_str()).unwrap_or("General"));
-    let plot = frame(ctx, area, CatAxis::Labels(&labels), &ValAxis { scale: ys, fmt: &f }, None, false, true);
+    let plot = frame(ctx, area, CatAxis::Labels(&labels), &ValAxis { scale: ys, fmt: &f }, None, false, chart.gridlines);
     if !plot.ok() {
         return;
     }
diff --git a/crates/chart/src/resolve.rs b/crates/chart/src/resolve.rs
index 2c17eff..c007e3e 100644
--- a/crates/chart/src/resolve.rs
+++ b/crates/chart/src/resolve.rs
@@ -16,6 +16,8 @@ pub(crate) const MAX_TRENDLINES: usize = 16;
 
 /// Tints used for series beyond the six theme accents: lighter, darker, lighter still…
 const CYCLE_TINTS: [f64; 6] = [0.0, 0.4, -0.25, 0.6, -0.5, 0.2];
+/// `series_color` repeats after this many colours (six accents × the tints).
+pub(crate) const PALETTE_CYCLE: usize = 6 * CYCLE_TINTS.len();
 
 /// Colour of the `i`-th series: theme accents 1–6, then tinted variations of them.
 pub fn series_color(theme: &Theme, i: usize) -> Rgba {
@@ -145,7 +147,7 @@ fn category_texts(wb: &Workbook, sheet: usize, formula: &str) -> Vec<String> {
                 if let Some(c) = at {
                     let code = &wb.styles.get(s.style_id(c)).num_fmt.0;
                     if !code.eq_ignore_ascii_case("general") {
-                        return format_value(v, &NumberFormat::parse(code), wb.date_system).text;
+                        return format_value(v, &NumberFormat::parse_cached(code), wb.date_system).text;
                     }
                 }
             }
@@ -239,5 +241,6 @@ pub fn resolve(wb: &Workbook, sheet: usize, chart: &Chart) -> ChartData {
     }
     let n = series.iter().map(|s| s.values.len()).max().unwrap_or(0);
     let categories = categories.unwrap_or_else(|| (1..=n).map(|i| i.to_string()).collect());
-    ChartData { categories, series }
+    let palette = default_palette(&wb.theme, n.min(PALETTE_CYCLE));
+    ChartData { categories, series, palette }
 }
diff --git a/crates/chart/src/tests.rs b/crates/chart/src/tests.rs
index a942677..1093e92 100644
--- a/crates/chart/src/tests.rs
+++ b/crates/chart/src/tests.rs
@@ -74,6 +74,7 @@ fn sample(kind: ChartKind) -> ChartData {
     let mut b = series("East", &[38000.0, 30000.0, 45000.0, 61870.0, 52000.0, 41000.0], [200, 80, 40, 255], k2);
     b.secondary = kind == ChartKind::Combo;
     ChartData {
+        palette: vec![],
         categories: cats.iter().map(|s| s.to_string()).collect(),
         series: vec![
             series("North", &[12000.0, -4000.0, 23000.0, 31000.0, 18000.0, 27000.0], [20, 96, 130, 255], k1),
@@ -362,7 +363,7 @@ fn scatter_with_text_x_values_numbers_the_points() {
         let d = resolve(&wb, 0, &c);
         assert_eq!(d.series[0].x, None, "{kind:?}");
         let prims = render(&c, &d, 400.0, 300.0, &ApproxMeasure);
-        let empty = render(&c, &ChartData { categories: vec![], series: vec![] }, 400.0, 300.0, &ApproxMeasure);
+        let empty = render(&c, &ChartData { palette: vec![], categories: vec![], series: vec![] }, 400.0, 300.0, &ApproxMeasure);
         assert!(prims.len() > empty.len() + 2, "{kind:?} draws its points");
         // Numeric X values are kept.
         c.series[0].categories = Some("Sheet1!$C$1:$C$3".into());
@@ -420,6 +421,16 @@ fn rasterize_bar_center_has_bar_color() {
     assert!(rasterize(&[], 100_000, 100_000, [0; 4]).is_empty());
 }
 
+#[test]
+fn rasterize_does_not_panic_on_negative_rect_extents() {
+    let red = [255, 0, 0, 255];
+    for (w, h) in [(-10.0, 10.0), (10.0, -10.0), (-10.0, -10.0), (f32::NAN, f32::NAN)] {
+        let rect = Prim::Rect { x: 5.0, y: 5.0, w, h, fill: Some(red), stroke: Some((red, 2.0)), radius: 0.0 };
+        let img = rasterize(&[rect], 20, 20, [0, 0, 0, 0]);
+        assert_eq!(img.len(), 20 * 20 * 4);
+    }
+}
+
 #[test]
 fn pie_starts_at_twelve_clockwise() {
     let c = chart(ChartKind::Pie);
@@ -445,7 +456,11 @@ fn pie_starts_at_twelve_clockwise() {
 #[test]
 fn negative_values_put_axis_below_zero() {
     let c = chart(ChartKind::ColumnClustered);
-    let d = ChartData { categories: vec![], series: vec![series("N", &[-5.0, 3.0, -2.0], [1, 2, 3, 255], ChartKind::ColumnClustered)] };
+    let d = ChartData {
+        palette: vec![],
+        categories: vec![],
+        series: vec![series("N", &[-5.0, 3.0, -2.0], [1, 2, 3, 255], ChartKind::ColumnClustered)],
+    };
     let prims = render(&c, &d, 400.0, 300.0, &ApproxMeasure);
     let t = texts(&prims);
     assert!(t.iter().any(|s| s.starts_with('-') || s.starts_with("($") || s.starts_with("-$")), "{t:?}");
@@ -456,8 +471,13 @@ fn negative_values_put_axis_below_zero() {
 fn edge_cases_never_panic() {
     let m = ApproxMeasure;
     let empty = ChartData::default();
-    let zeros = ChartData { categories: vec!["a".into(), "b".into()], series: vec![series("z", &[0.0, 0.0], [0, 0, 0, 255], ChartKind::Line)] };
+    let zeros = ChartData {
+        palette: vec![],
+        categories: vec!["a".into(), "b".into()],
+        series: vec![series("z", &[0.0, 0.0], [0, 0, 0, 255], ChartKind::Line)],
+    };
     let weird = ChartData {
+        palette: vec![],
         categories: vec![String::new(); 3],
         series: vec![SeriesData {
             name: "w".repeat(500),
@@ -488,7 +508,7 @@ fn thousands_of_points_are_decimated() {
     let vals: Vec<f64> = (0..n).map(|i| ((i as f64) * 0.01).sin() * 100.0 + i as f64 * 0.001).collect();
     let mut c = chart(ChartKind::Line);
     c.data_labels = true;
-    let d = ChartData { categories: vec![], series: vec![series("big", &vals, [9, 9, 9, 255], ChartKind::Line)] };
+    let d = ChartData { palette: vec![], categories: vec![], series: vec![series("big", &vals, [9, 9, 9, 255], ChartKind::Line)] };
     let prims = render(&c, &d, 800.0, 400.0, &ApproxMeasure);
     let max_line = prims
         .iter()
@@ -513,7 +533,7 @@ fn smooth_line_adds_interpolated_points_and_keeps_endpoints() {
     let line_pts = |smooth: bool, m: &ApproxMeasure| -> usize {
         let mut s = series("L", &[1.0, 5.0, 2.0, 6.0], [10, 20, 30, 255], ChartKind::Line);
         s.smooth = smooth;
-        let d = ChartData { categories: cats.clone(), series: vec![s] };
+        let d = ChartData { palette: vec![], categories: cats.clone(), series: vec![s] };
         render(&chart(ChartKind::Line), &d, 600.0, 400.0, m)
             .iter()
             .filter_map(|p| match p {
@@ -530,7 +550,7 @@ fn smooth_line_adds_interpolated_points_and_keeps_endpoints() {
     // Rendering either way must stay finite and inside the canvas.
     let mut s = series("L", &[1.0, 5.0, 2.0, 6.0], [10, 20, 30, 255], ChartKind::Line);
     s.smooth = true;
-    let d = ChartData { categories: cats, series: vec![s] };
+    let d = ChartData { palette: vec![], categories: cats, series: vec![s] };
     assert_sane(&render(&chart(ChartKind::Line), &d, 600.0, 400.0, &m), 600.0, 400.0);
 }
 
@@ -540,7 +560,7 @@ fn smooth_line_splits_at_gaps() {
     let mut s = series("L", &[1.0, 5.0, 2.0, 6.0], [10, 20, 30, 255], ChartKind::Line);
     s.smooth = true;
     s.values[1] = None; // gap between two data points
-    let d = ChartData { categories: vec!["a".into(), "b".into(), "c".into(), "d".into()], series: vec![s] };
+    let d = ChartData { palette: vec![], categories: vec!["a".into(), "b".into(), "c".into(), "d".into()], series: vec![s] };
     let prims = render(&chart(ChartKind::Line), &d, 600.0, 400.0, &m);
     // Two separate runs (before/after the gap) → at least two line primitives.
     let lines = prims.iter().filter(|p| matches!(p, Prim::Line { .. })).count();
@@ -617,7 +637,7 @@ fn fuzz_random_data_and_sizes() {
             })
             .collect();
         let ncat = (r.next() % 50) as usize;
-        let d = ChartData { categories: (0..ncat).map(|i| "c".repeat(i % 7) + &i.to_string()).collect(), series };
+        let d = ChartData { palette: vec![], categories: (0..ncat).map(|i| "c".repeat(i % 7) + &i.to_string()).collect(), series };
         let mut c = chart(kind);
         c.legend = [LegendPos::None, LegendPos::Bottom, LegendPos::Top, LegendPos::Left, LegendPos::Right][(r.next() % 5) as usize];
         c.data_labels = r.next().is_multiple_of(2);
@@ -792,7 +812,7 @@ fn line_chart_draws_trendline_forecast_and_labels() {
     let mut s = series("Sales", &[9.0, 7.0, 5.0, 3.0], [10, 20, 30, 255], ChartKind::Line);
     s.trendlines =
         vec![TrendlineData { spec: Trendline { forward: 1.0, display_equation: true, display_r_squared: true, ..Trendline::default() }, color: tc }];
-    let d = ChartData { categories: ["a", "b", "c", "d"].map(String::from).to_vec(), series: vec![s.clone()] };
+    let d = ChartData { palette: vec![], categories: ["a", "b", "c", "d"].map(String::from).to_vec(), series: vec![s.clone()] };
     let mut c = chart(ChartKind::Line);
     c.legend = LegendPos::None; // keeps legend swatches out of the line counts
     let prims = render(&c, &d, 600.0, 400.0, &m);
@@ -816,7 +836,7 @@ fn line_chart_draws_trendline_forecast_and_labels() {
     assert!(lines_of(&pie, tc).is_empty());
     // One point: nothing to fit, nothing drawn.
     s.values.truncate(1);
-    let one = ChartData { categories: vec!["a".into()], series: vec![s] };
+    let one = ChartData { palette: vec![], categories: vec!["a".into()], series: vec![s] };
     assert!(lines_of(&render(&c, &one, 600.0, 400.0, &m), tc).is_empty());
 }
 
@@ -836,7 +856,7 @@ fn scatter_trendlines_use_x_values_and_stay_in_the_plot() {
         TrendlineData { spec: Trendline { kind: TrendlineKind::Exponential, forward: 30.0, ..Trendline::default() }, color: colors[1] },
         TrendlineData { spec: Trendline { kind: TrendlineKind::MovingAverage(2), ..Trendline::default() }, color: colors[2] },
     ];
-    let d = ChartData { categories: vec![], series: vec![s] };
+    let d = ChartData { palette: vec![], categories: vec![], series: vec![s] };
     let mut c = chart(ChartKind::Scatter);
     c.legend = LegendPos::None;
     let prims = render(&c, &d, 600.0, 400.0, &m);
@@ -851,6 +871,7 @@ fn scatter_trendlines_use_x_values_and_stay_in_the_plot() {
 #[test]
 fn treemap_and_histogram_shapes() {
     let d = ChartData {
+        palette: vec![],
         categories: vec!["a".into(), "b".into(), "c".into(), "d".into()],
         series: vec![series("t", &[6.0, 6.0, 4.0, 3.0], [10, 20, 30, 255], ChartKind::Treemap)],
     };
@@ -871,12 +892,34 @@ fn treemap_and_histogram_shapes() {
     assert!((rects[0] / rects[3] - 2.0).abs() < 0.05, "{rects:?}");
 
     let vals: Vec<f64> = (0..100).map(|i| i as f64).collect();
-    let d = ChartData { categories: vec![], series: vec![series("h", &vals, [10, 20, 30, 255], ChartKind::Histogram)] };
+    let d = ChartData { palette: vec![], categories: vec![], series: vec![series("h", &vals, [10, 20, 30, 255], ChartKind::Histogram)] };
     let prims = render(&chart(ChartKind::Histogram), &d, 600.0, 400.0, &ApproxMeasure);
     let bins = prims.iter().filter(|p| matches!(p, Prim::Rect { fill: Some([10, 20, 30, 255]), .. })).count();
     assert_eq!(bins, 10);
 }
 
+#[test]
+fn histogram_boundary_values_match_interval_labels() {
+    let heights = |vals: &[f64]| -> Vec<f32> {
+        let d = ChartData { categories: vec![], series: vec![series("h", vals, [10, 20, 30, 255], ChartKind::Histogram)] };
+        let prims = render(&chart(ChartKind::Histogram), &d, 600.0, 400.0, &ApproxMeasure);
+        prims.iter().filter_map(|p| if let Prim::Rect { h, fill: Some([10, 20, 30, 255]), .. } = p { Some(*h) } else { None }).collect()
+    };
+    // Labels are "[0, 7.5]" and "(7.5, 15.0]": 7.5 belongs to the first bar, so the counts are 2 and 1.
+    let h = heights(&[0.0, 7.5, 15.0]);
+    assert_eq!(h.len(), 2);
+    assert!((h[0] / h[1] - 2.0).abs() < 0.01, "{h:?}");
+    let h = heights(&[-15.0, -7.5, 0.0]);
+    assert!((h[0] / h[1] - 2.0).abs() < 0.01, "{h:?}");
+    // A value off the boundary still goes right: [0, 7.5] holds 1, (7.5, 15.0] holds 2.
+    let h = heights(&[0.0, 7.75, 15.0]);
+    assert!((h[1] / h[0] - 2.0).abs() < 0.01, "{h:?}");
+    // Five values, three bins [0,5] (5,10] (10,15]: counts 3, 1, 1.
+    let h = heights(&[0.0, 5.0, 5.0, 10.0, 15.0]);
+    assert_eq!(h.len(), 3);
+    assert!((h[0] / h[1] - 3.0).abs() < 0.01 && (h[1] - h[2]).abs() < 0.01, "{h:?}");
+}
+
 #[test]
 fn union_series_references() {
     let mut wb = Workbook::new();
@@ -902,3 +945,106 @@ fn union_series_references() {
     c.series[0].values = format!("{}Sheet1!$B$1,Sheet1!$B$2{}", "(".repeat(5000), ")".repeat(5000));
     let _ = resolve(&wb, 0, &c);
 }
+
+#[test]
+fn box_and_stock_charts_honour_the_gridlines_flag() {
+    // Horizontal full-width lines in the gridline colour are the value-axis gridlines.
+    let grid: Rgba = [217, 217, 217, 255];
+    let is_grid = |p: &Prim| match p {
+        Prim::Line { color, pts, .. } => *color == grid && pts.len() == 2 && pts[0][1] == pts[1][1] && pts[1][0] - pts[0][0] > 200.0,
+        _ => false,
+    };
+    let grids = |prims: &[Prim]| prims.iter().filter(|p| is_grid(p)).count();
+    for kind in [ChartKind::BoxWhisker, ChartKind::Stock, ChartKind::ColumnClustered] {
+        let mut d = sample(kind);
+        d.series.push(series("Close", &[10000.0, 12000.0, 9000.0, 14000.0, 20000.0, 16000.0], [90, 90, 90, 255], kind));
+        let mut c = chart(kind);
+        let on = render(&c, &d, 500.0, 350.0, &ApproxMeasure);
+        c.gridlines = false;
+        let off = render(&c, &d, 500.0, 350.0, &ApproxMeasure);
+        assert!(grids(&on) > 0, "{kind:?}: gridlines on must draw lines");
+        assert_eq!(grids(&off), 0, "{kind:?}: gridlines off must hide them");
+fn funnel_value_labels_follow_the_data_labels_flag() {
+    let data = ChartData {
+        categories: vec!["a".into(), "b".into(), "c".into()],
+        series: vec![series("S", &[11111.0, 22222.0, 33333.0], [20, 96, 130, 255], ChartKind::Funnel)],
+    };
+    let mut c = chart(ChartKind::Funnel);
+    c.data_labels = false;
+    let off = render(&c, &data, 500.0, 350.0, &ApproxMeasure);
+    c.data_labels = true;
+    let on = render(&c, &data, 500.0, 350.0, &ApproxMeasure);
+    let values = ["$11,111", "$22,222", "$33,333"];
+    for v in values {
+        assert!(texts(&on).contains(&v), "{v} missing with labels on");
+        assert!(!texts(&off).contains(&v), "{v} drawn with labels off");
+    }
+    for cat in ["a", "b", "c"] {
+        assert!(texts(&off).contains(&cat));
+        assert!(texts(&on).contains(&cat));
+fn pie_points_follow_workbook_theme() {
+    let mut wb = Workbook::new();
+    wb.theme.colors[4] = 0x4F6D8A;
+    wb.theme.colors[5] = 0x8AA1B8;
+    let mut c = chart(ChartKind::Pie);
+    c.series = vec![Series {
+        name: None,
+        categories: None,
+        values: "{5,3}".into(),
+        bubble_sizes: None,
+        color: None,
+        secondary: false,
+        kind: None,
+        smooth: false,
+        trendlines: Vec::new(),
+    }];
+    let d = resolve(&wb, 0, &c);
+    let expected = vec![series_color(&wb.theme, 0), series_color(&wb.theme, 1)];
+    assert_eq!(expected, vec![[0x4F, 0x6D, 0x8A, 0xFF], [0x8A, 0xA1, 0xB8, 0xFF]]);
+    let legend: Vec<Rgba> = legend_entries(&c, &d).iter().map(|e| e.1).collect();
+    assert_eq!(legend, expected);
+    let fills: Vec<Rgba> = render(&c, &d, 480.0, 288.0, &ApproxMeasure)
+        .iter()
+        .filter_map(|p| match p {
+            Prim::Wedge { fill, .. } => Some(*fill),
+            _ => None,
+        })
+        .collect();
+    assert_eq!(fills, expected);
+    for kind in [ChartKind::Doughnut, ChartKind::Treemap, ChartKind::Sunburst] {
+        c.kind = kind;
+        let legend: Vec<Rgba> = legend_entries(&c, &d).iter().map(|e| e.1).collect();
+        assert_eq!(legend, expected, "{kind:?}");
+    }
+    // Past the 36-colour cycle the points keep following the workbook theme.
+    c.kind = ChartKind::Pie;
+    c.series[0].values = format!("{{{}}}", ["1"; 40].join(","));
+    let d = resolve(&wb, 0, &c);
+    let legend: Vec<Rgba> = legend_entries(&c, &d).iter().map(|e| e.1).collect();
+    assert_eq!(legend.len(), 40);
+    assert_eq!(legend.get(37), Some(&series_color(&wb.theme, 37)));
+    assert_ne!(series_color(&wb.theme, 37), series_color(&gridcraft_model::Theme::default(), 37));
+fn area_charts_draw_source_value_labels_only_when_enabled() {
+    for kind in [ChartKind::Area, ChartKind::AreaStacked] {
+        let d = sample(kind);
+        let mut c = chart(kind);
+        c.data_labels = false;
+        let off = render(&c, &d, 640.0, 400.0, &ApproxMeasure);
+        c.data_labels = true;
+        let on = render(&c, &d, 640.0, 400.0, &ApproxMeasure);
+        let count = |p: &[Prim], v: &str| texts(p).iter().filter(|t| **t == v).count();
+        // One label per point: 3 series x 6 categories.
+        assert_eq!(texts(&on).len(), texts(&off).len() + 18, "{kind:?}");
+        for v in ["$12,000", "$38,000", "$9,000", "$27,000"] {
+            assert_eq!(count(&on, v), count(&off, v) + 1, "{kind:?}: {v}");
+        }
+        // Stacked areas label the source values, not cumulative totals (12,000 + 38,000).
+        assert_eq!(count(&on, "$50,000"), count(&off, "$50,000"), "{kind:?}: cumulative total shown");
+        let polys = |p: &[Prim]| p.iter().filter(|p| matches!(p, Prim::Polygon { .. })).cloned().collect::<Vec<_>>();
+        assert_eq!(polys(&on), polys(&off));
+        // The first series' labels are drawn after every area, so the next area can't cover them.
+        let last_poly = on.iter().rposition(|p| matches!(p, Prim::Polygon { .. }));
+        let first_label = on.iter().position(|p| matches!(p, Prim::Text { text, .. } if text == "$12,000"));
+        assert!(first_label > last_poly, "{kind:?}: label drawn under a later area");
+    }
+}
diff --git a/crates/core/src/date.rs b/crates/core/src/date.rs
index 3b126b7..b61892f 100644
--- a/crates/core/src/date.rs
+++ b/crates/core/src/date.rs
@@ -59,6 +59,14 @@ pub fn serial_from_unix_ms(ms: f64) -> f64 {
     25569.0 + ms / 86_400_000.0
 }
 
+/// Converts a 1900-system serial (as the clock supplies it) to the serial of the same instant in `sys`.
+pub fn serial_in_system(sys: DateSystem, serial_1900: f64) -> f64 {
+    match sys {
+        DateSystem::D1900 => serial_1900,
+        DateSystem::D1904 => serial_1900 - 1462.0,
+    }
+}
+
 pub fn civil_from_days(z: i64) -> (i32, u32, u32) {
     let z = z + 719468;
     let era = if z >= 0 { z } else { z - 146096 } / 146097;
@@ -95,6 +103,14 @@ pub fn days_in_month_in(sys: DateSystem, y: i32, m: u32) -> u32 {
     if sys == DateSystem::D1900 && y == 1900 && m == 2 { 29 } else { days_in_month(y, m) }
 }
 
+/// Last serial that is a valid date in a date system: 9999-12-31 (2958465 in the 1900 system, 2957003 in the 1904 system).
+pub fn max_serial(sys: DateSystem) -> i64 {
+    match sys {
+        DateSystem::D1900 => 2_958_465,
+        DateSystem::D1904 => 2_958_465 - 1462,
+    }
+}
+
 /// Serial for a date. Month and day overflow roll over like `DATE()` (month 13 = January next
 /// year, day 0 = last day of the previous month), in the date system's own calendar: in the 1900
 /// system February 1900 has 29 days, so `(1900, 2, 29)` and `(1900, 3, 0)` are serial 60.
@@ -117,7 +133,7 @@ pub fn serial_from_ymd(sys: DateSystem, year: i64, month: i64, day: i64) -> Opti
         DateSystem::D1904 => first - UNIX_1904_01_01,
     };
     let serial = first.checked_add(day)?.checked_sub(1)?;
-    if !(0..=2_958_465).contains(&serial) {
+    if !(0..=max_serial(sys)).contains(&serial) {
         return None;
     }
     Some(serial as f64)
@@ -125,7 +141,7 @@ pub fn serial_from_ymd(sys: DateSystem, year: i64, month: i64, day: i64) -> Opti
 
 /// Date/time from a serial. `None` for negative or too-large serials.
 pub fn datetime_from_serial(sys: DateSystem, serial: f64) -> Option<DateTime> {
-    if !serial.is_finite() || !(0.0..2_958_466.0).contains(&serial) {
+    if !serial.is_finite() || !(0.0..max_serial(sys) as f64 + 1.0).contains(&serial) {
         return None;
     }
     let mut day = serial.floor() as i64;
@@ -197,6 +213,10 @@ mod tests {
         assert_eq!(serial_from_ymd(s, 2000, 1, 1), Some(36526.0));
         assert_eq!(serial_from_ymd(s, 2026, 10, 7), Some(46302.0));
         assert_eq!(serial_from_ymd(s, 9999, 12, 31), Some(2958465.0));
+        assert_eq!(serial_from_ymd(DateSystem::D1904, 9999, 12, 31), Some(2957003.0));
+        assert_eq!(serial_from_ymd(DateSystem::D1904, 9999, 12, 32), None);
+        assert!(datetime_from_serial(DateSystem::D1904, 2957003.5).is_some());
+        assert!(datetime_from_serial(DateSystem::D1904, 2957004.0).is_none());
         assert_eq!(serial_from_ymd(s, 2020, 13, 1), serial_from_ymd(s, 2021, 1, 1));
         assert_eq!(serial_from_ymd(s, 2020, 3, 0), serial_from_ymd(s, 2020, 2, 29));
         assert_eq!(serial_from_ymd(s, 120, 1, 1), serial_from_ymd(s, 2020, 1, 1));
diff --git a/crates/core/src/parse.rs b/crates/core/src/parse.rs
index a612a0b..a943103 100644
--- a/crates/core/src/parse.rs
+++ b/crates/core/src/parse.rs
@@ -252,10 +252,14 @@ fn parse_date(t: &str, sys: DateSystem) -> Option<(f64, &'static str)> {
     // "Mar 4, 2026" / "March 4 2026" / "4 March 2026"
     let words: Vec<&str> = t.split([' ', ',']).filter(|w| !w.is_empty()).collect();
     if words.len() == 3 {
+        // Two-digit years follow the same 2029 rule as the dashed forms above.
+        let expand = |w: &str, y: i64| if w.len() <= 2 { if y < 30 { 2000 + y } else { 1900 + y } } else { y };
         if let (Some(m), Some(d), Some(y)) = (month_from_name(words[0]), num(words[1]), num(words[2])) {
+            let y = expand(words[2], y);
             return valid_ymd(sys, y, m as i64, d).map(|s| (s, "d-mmm-yy"));
         }
         if let (Some(d), Some(m), Some(y)) = (num(words[0]), month_from_name(words[1]), num(words[2])) {
+            let y = expand(words[2], y);
             return valid_ymd(sys, y, m as i64, d).map(|s| (s, "d-mmm-yy"));
         }
     }
@@ -317,6 +321,16 @@ mod tests {
         parse_input(s, DateSystem::D1900)
     }
 
+    #[test]
+    fn month_name_short_year() {
+        for s in ["Mar 4, 26", "Mar 4 26", "March 4 26", "4 March 26", "Mar 4, 2026"] {
+            assert_eq!(p(s).value, Value::Number(46085.0), "{s}");
+        }
+        assert_eq!(p("Mar 4, 99").value, p("Mar 4, 1999").value);
+        assert_eq!(p("Mar 4, 1776").value, Value::text("Mar 4, 1776"));
+        assert_eq!(p("Feb 30, 26").value, Value::text("Feb 30, 26"));
+    }
+
     #[test]
     fn numbers() {
         assert_eq!(p("42").value, Value::Number(42.0));
diff --git a/crates/engine/src/cf.rs b/crates/engine/src/cf.rs
index 21a32dd..b71ddb8 100644
--- a/crates/engine/src/cf.rs
+++ b/crates/engine/src/cf.rs
@@ -184,7 +184,7 @@ impl CfCache {
                 },
                 CfRule::TimePeriod { period, style } => match v.as_f64() {
                     Some(n) => {
-                        let today = gridcraft_calc::now_serial().floor();
+                        let today = gridcraft_core::date::serial_in_system(wb.date_system, gridcraft_calc::now_serial()).floor();
                         let d = n.floor();
                         let wd = gridcraft_core::date::datetime_from_serial(wb.date_system, today).map(|x| x.weekday as f64).unwrap_or(0.0);
                         let week_start = today - wd;
diff --git a/crates/engine/src/cmd/data.rs b/crates/engine/src/cmd/data.rs
index e4aa3ba..311121e 100644
--- a/crates/engine/src/cmd/data.rs
+++ b/crates/engine/src/cmd/data.rs
@@ -198,27 +198,29 @@ fn sort(s: &mut Session, p: &Json) -> Result<Json> {
     let header = bool_param(p, "header").unwrap_or_else(|| guess_header(&d.wb, sh, r));
     let by_cols = str_param(p, "orientation") == Some("columns");
     let case = bool_param(p, "matchCase").unwrap_or(false);
-    let keys: Vec<SortKey> = p
-        .get("keys")
-        .and_then(Json::as_array)
-        .map(|a| {
-            a.iter()
-                .filter_map(|k| {
-                    let col = if by_cols {
-                        k.get("row").and_then(Json::as_u64).map(|r| r as u32 - 1).or_else(|| col_param(k.get("column"), r.start.row))?
-                    } else {
-                        col_param(k.get("column"), r.start.col)?
-                    };
-                    Some(SortKey {
-                        col,
-                        desc: k.get("order").and_then(Json::as_str) == Some("desc"),
-                        by: k.get("by").and_then(Json::as_str).unwrap_or("values").to_string(),
-                        list: k.get("customList").and_then(Json::as_array).map(|l| l.iter().filter_map(|x| x.as_str().map(str::to_string)).collect()),
-                    })
-                })
-                .collect()
-        })
-        .unwrap_or_default();
+    let mut keys: Vec<SortKey> = Vec::new();
+    for k in p.get("keys").and_then(Json::as_array).map(Vec::as_slice).unwrap_or_default() {
+        let col = if by_cols {
+            let row = match k.get("row").and_then(Json::as_u64) {
+                // Worksheet rows are 1-based; 0 (or a value past u32) has no coordinate.
+                Some(n) => {
+                    let row = u32::try_from(n).ok().and_then(|n| n.checked_sub(1));
+                    Some(row.ok_or_else(|| bad("data.sort", "sort key row must be 1 or greater"))?)
+                }
+                None => None,
+            };
+            row.or_else(|| col_param(k.get("column"), r.start.row))
+        } else {
+            col_param(k.get("column"), r.start.col)
+        };
+        let Some(col) = col else { continue };
+        keys.push(SortKey {
+            col,
+            desc: k.get("order").and_then(Json::as_str) == Some("desc"),
+            by: k.get("by").and_then(Json::as_str).unwrap_or("values").to_string(),
+            list: k.get("customList").and_then(Json::as_array).map(|l| l.iter().filter_map(|x| x.as_str().map(str::to_string)).collect()),
+        });
+    }
     if keys.is_empty() {
         s.ui_requests.push(crate::UiRequest::Dialog("sort".into(), json!({"range": r.a1(), "header": header})));
         return ok();
@@ -454,14 +456,24 @@ fn toggle_filter(s: &mut Session, p: &Json) -> Result<Json> {
     if has {
         return edit(s, |cx| {
             let sh = cx.sheet_mut(sheet)?;
+            // Reveal only rows the filter hid; rows hidden by hand or by a collapsed group stay hidden.
+            let filtered: Vec<u32> = sh.rows.keys().copied().filter(|r| sh.is_row_filtered(*r)).collect();
             sh.autofilter = None;
-            for info in sh.rows.values_mut() {
-                info.hidden = false;
+            for r in filtered {
+                if let Some(info) = sh.rows.get_mut(&r) {
+                    info.hidden = false;
+                }
             }
             cx.structural = true;
             Ok(json!({"filter": false}))
         });
     }
+    install_filter(s, p)
+}
+
+/// Turn a sheet AutoFilter on over `p.range`, or over the data range of the selection.
+fn install_filter(s: &mut Session, p: &Json) -> Result<Json> {
+    let sheet = s.doc()?.wb.active_sheet;
     let mut r = data_range(s, p)?;
     // A selected header row filters the data below it (#201).
     if p.get("range").is_none() && r.height() == 1 {
@@ -484,7 +496,7 @@ fn filter_by(s: &mut Session, p: &Json) -> Result<Json> {
     let af = match &sh.autofilter {
         Some(a) => a.clone(),
         None => {
-            toggle_filter(s, &json!({}))?;
+            install_filter(s, &json!({}))?;
             s.doc()?.wb.sheet(sheet).and_then(|sh| sh.autofilter.clone()).ok_or_else(|| EngineError::Other("no filter".into()))?
         }
     };
@@ -570,19 +582,28 @@ pub(crate) fn apply_filter(wb: &mut Workbook, sheet: usize) {
     let Some(af) = sh.autofilter.clone() else { return };
     let r = af.range;
     let mut hide = Vec::new();
-    // Precompute per-column numbers for top10/average.
-    let mut col_stats: std::collections::HashMap<u32, (Vec<f64>, f64)> = std::collections::HashMap::new();
-    for (off, c) in &af.criteria {
+    // Precompute per-criterion top10 threshold and average once, not per row.
+    let mut col_stats: std::collections::HashMap<usize, (Option<f64>, f64)> = std::collections::HashMap::new();
+    for (i, (off, c)) in af.criteria.iter().enumerate() {
         if matches!(c, FilterCriterion::Top10 { .. } | FilterCriterion::AboveAverage(_)) {
             let col = r.start.col + off;
-            let nums: Vec<f64> = (r.start.row + 1..=r.end.row).filter_map(|row| sh.value(CellRef::new(row, col)).as_f64()).collect();
+            let mut nums: Vec<f64> = (r.start.row + 1..=r.end.row).filter_map(|row| sh.value(CellRef::new(row, col)).as_f64()).collect();
             let avg = if nums.is_empty() { 0.0 } else { nums.iter().sum::<f64>() / nums.len() as f64 };
-            col_stats.insert(*off, (nums, avg));
+            let thr = match c {
+                FilterCriterion::Top10 { bottom, percent, count } => {
+                    nums.sort_by(|a, b| if *bottom { a.partial_cmp(b) } else { b.partial_cmp(a) }.unwrap_or(Ordering::Equal));
+                    let k = if *percent { ((nums.len() as f64) * (*count as f64) / 100.0).ceil() as usize } else { *count as usize };
+                    let k = k.clamp(1, nums.len().max(1));
+                    nums.get(k - 1).copied()
+                }
+                _ => None,
+            };
+            col_stats.insert(i, (thr, avg));
         }
     }
     for row in r.start.row + 1..=r.end.row {
         let mut visible = true;
-        for (off, crit) in &af.criteria {
+        for (i, (off, crit)) in af.criteria.iter().enumerate() {
             let c = CellRef::new(row, r.start.col + off);
             let v = sh.value(c);
             let text = crate::display::cell_text(wb, sh, c);
@@ -604,18 +625,14 @@ pub(crate) fn apply_filter(wb: &mut Workbook, sheet: usize) {
                         None => x,
                     }
                 }
-                FilterCriterion::Top10 { bottom, percent, count } => match (v.as_f64(), col_stats.get(off)) {
-                    (Some(n), Some((nums, _))) => {
-                        let mut sorted = nums.clone();
-                        sorted.sort_by(|a, b| if *bottom { a.partial_cmp(b) } else { b.partial_cmp(a) }.unwrap_or(Ordering::Equal));
-                        let k = if *percent { ((sorted.len() as f64) * (*count as f64) / 100.0).ceil() as usize } else { *count as usize };
-                        let k = k.clamp(1, sorted.len().max(1));
-                        let thr = sorted.get(k - 1).copied().unwrap_or(n);
+                FilterCriterion::Top10 { bottom, .. } => match (v.as_f64(), col_stats.get(&i)) {
+                    (Some(n), Some((thr, _))) => {
+                        let thr = thr.unwrap_or(n);
                         if *bottom { n <= thr } else { n >= thr }
                     }
                     _ => false,
                 },
-                FilterCriterion::AboveAverage(above) => match (v.as_f64(), col_stats.get(off)) {
+                FilterCriterion::AboveAverage(above) => match (v.as_f64(), col_stats.get(&i)) {
                     (Some(n), Some((_, avg))) => {
                         if *above {
                             n > *avg
@@ -896,7 +913,7 @@ fn subtract_range(r: RangeRef, cut: &RangeRef) -> Vec<RangeRef> {
 }
 
 /// Removes the cells of `cuts` from every validation, keeping the rest of each rule's ranges.
-fn remove_validation_cells(validations: &mut Vec<Validation>, cuts: &[RangeRef]) {
+pub(super) fn remove_validation_cells(validations: &mut Vec<Validation>, cuts: &[RangeRef]) {
     for dv in validations.iter_mut() {
         for cut in cuts {
             dv.ranges = dv.ranges.iter().flat_map(|r| subtract_range(*r, cut)).collect();
@@ -1046,6 +1063,18 @@ fn formula_at(f: &str, first: CellRef, at: CellRef) -> String {
     }
 }
 
+/// Moves the relative references of a rule formula written for `first` so it reads the same cells from `to`
+/// (pasting a rule); text without relative references (constants, literal lists) stays as typed.
+pub(super) fn move_rule_formula(f: &str, first: CellRef, to: CellRef) -> String {
+    if first == to {
+        return f.to_string();
+    }
+    let moved = formula_at(f, first, to);
+    let has_relative = gridcraft_formula::parse(f.trim_start_matches('=')).is_ok_and(|e| gridcraft_formula::print(&e) != moved);
+    let eq = if f.starts_with('=') { "=" } else { "" };
+    if has_relative { format!("{eq}{moved}") } else { f.to_string() }
+}
+
 fn compare_op(op: CfOperator, n: f64, a: Option<f64>, b: Option<f64>) -> bool {
     let Some(a) = a else { return false };
     match op {
@@ -1129,6 +1158,7 @@ fn group(s: &mut Session, p: &Json, on: bool) -> Result<Json> {
         {
             e.collapsed = false;
         }
+        cx.structural = true; // ungrouping reveals hidden rows: SUBTOTAL(10x) depends on it
         Ok(Json::Null)
     })
 }
@@ -1278,6 +1308,24 @@ fn subtotal(s: &mut Session, p: &Json) -> Result<Json> {
 mod tests {
     use super::*;
 
+    #[test]
+    fn filter_by_inside_a_table_installs_the_autofilter_and_keeps_the_button() {
+        for sel in [json!({"cell": "A1"}), json!({"cell": "A2"}), json!({"range": "A1:A3"})] {
+            let mut s = Session::new();
+            s.new_workbook();
+            s.execute("range.setValues", json!({"range": "A1", "values": [["H"], ["a"], ["b"]]})).unwrap();
+            s.execute("insert.table", json!({"range": "A1:A3", "header": true})).unwrap();
+            s.execute("selection.set", sel.clone()).unwrap();
+            s.execute("data.filterBy", json!({"column": "A", "values": ["a"]})).unwrap();
+            let sh = s.doc().unwrap().wb.active().unwrap();
+            assert_eq!(sh.autofilter.as_ref().map(|a| a.range.a1()), Some("A1:A3".to_string()), "{sel}");
+            assert!(sh.tables[0].filter_button, "{sel}");
+            assert!(!sh.is_row_hidden(1), "{sel}");
+            assert!(sh.is_row_hidden(2), "{sel}");
+            assert_eq!(sh.value(CellRef::new(2, 0)).display(), "b", "{sel}");
+        }
+    }
+
     #[test]
     fn partial_validation_edits_keep_the_rest_of_the_old_rule() {
         let mut s = Session::new();
@@ -1300,6 +1348,45 @@ mod tests {
         assert!(!ok(&mut s, "B1", "150"));
     }
 
+    #[test]
+    fn removing_an_autofilter_keeps_manually_hidden_and_collapsed_rows() {
+        let mut s = Session::new();
+        s.new_workbook();
+        s.execute("range.setValues", json!({"range": "A1", "values": [["H"], ["a"], ["b"], ["c"]]})).unwrap();
+        s.execute("range.setValues", json!({"range": "A10", "values": [["z"]]})).unwrap();
+        s.execute("data.group", json!({"rows": "2:4"})).unwrap();
+        s.execute("data.hideDetail", json!({"rows": "2:4"})).unwrap();
+        s.execute("home.hideRows", json!({"rows": "10:10"})).unwrap();
+        let hidden = |s: &Session| -> Vec<u32> {
+            let sh = s.doc().unwrap().wb.active().unwrap();
+            sh.rows.iter().filter(|(_, l)| l.hidden).map(|(r, _)| *r).collect()
+        };
+        let before = hidden(&s);
+        assert_eq!(before, [1, 2, 3, 9]);
+        s.execute("data.filter", json!({"range": "A1:A4"})).unwrap();
+        s.execute("data.filter", json!({"range": "A1:A4"})).unwrap();
+        assert!(s.doc().unwrap().wb.active().unwrap().autofilter.is_none());
+        assert_eq!(hidden(&s), before);
+        assert_eq!(row_state(&s, 4..=4), [(false, true)]);
+    }
+
+    #[test]
+    fn table_dropdown_setup_outside_the_table_keeps_manually_hidden_rows() {
+        let mut s = Session::new();
+        s.new_workbook();
+        s.execute("range.setValues", json!({"range": "A1", "values": [["H"], ["a"], ["b"], ["c"]]})).unwrap();
+        s.execute("range.setValues", json!({"range": "A10", "values": [["z"]]})).unwrap();
+        s.execute("insert.table", json!({"range": "A1:A4", "header": true})).unwrap();
+        s.execute("home.hideRows", json!({"rows": "3:3"})).unwrap();
+        s.execute("home.hideRows", json!({"rows": "10:10"})).unwrap();
+        s.execute("selection.set", json!({"range": "E1"})).unwrap();
+        // The table filter dropdown installs an AutoFilter on demand by toggling `data.filter` twice.
+        s.execute("data.filter", json!({"range": "A1:A4"})).unwrap();
+        s.execute("data.filter", json!({"range": "A1:A4"})).unwrap();
+        let sh = s.doc().unwrap().wb.active().unwrap();
+        assert_eq!(sh.rows.iter().filter(|(_, l)| l.hidden).map(|(r, _)| *r).collect::<Vec<_>>(), [2, 9]);
+    }
+
     /// Rows 5:8 grouped, with 6:7 grouped again inside (0-based 4..=7 and 5..=6).
     fn nested_rows() -> Session {
         let mut s = Session::new();
@@ -1375,6 +1462,18 @@ mod tests {
         assert_eq!(sc("data.ungroup"), Some("Alt+Shift+Left"));
     }
 
+    #[test]
+    fn column_sort_rejects_row_key_zero_without_panicking() {
+        let mut s = Session::new();
+        s.new_workbook();
+        s.execute("cell.set", json!({"cell": "A1", "input": "2"})).unwrap();
+        for row in [0u64, 1 << 32] {
+            let params = json!({"range": "A1:B2", "header": false, "orientation": "columns", "keys": [{"row": row}]});
+            let err = s.execute("data.sort", params).unwrap_err();
+            assert!(matches!(err, EngineError::BadParams { .. }), "row {row}: {err:?}");
+        }
+    }
+
     #[test]
     fn split() {
         assert_eq!(split_delimited("a,b,,c", &[','], false, '"'), ["a", "b", "", "c"]);
diff --git a/crates/engine/src/cmd/edit.rs b/crates/engine/src/cmd/edit.rs
index 3da230b..0b467e0 100644
--- a/crates/engine/src/cmd/edit.rs
+++ b/crates/engine/src/cmd/edit.rs
@@ -219,11 +219,8 @@ fn cell_set(s: &mut Session, p: &Json) -> Result<Json> {
         Some(c) => c,
         None => s.doc()?.selection.active,
     };
-    let input = str_param(p, "input")
-        .or_else(|| str_param(p, "value"))
-        .map(str::to_string)
-        .or_else(|| p.get("value").map(json_to_input))
-        .ok_or_else(|| bad("cell.set", "missing `input` (or `value`)"))?;
+    // Both spellings take a string, number or boolean, as typed (#697).
+    let input = p.get("input").or_else(|| p.get("value")).map(json_to_input).ok_or_else(|| bad("cell.set", "missing `input` (or `value`)"))?;
     let array = bool_param(p, "array").unwrap_or(false);
     let d = s.doc()?;
     if let Some(sh) = d.wb.sheet(sheet)
@@ -420,14 +417,7 @@ fn selection_move(s: &mut Session, p: &Json) -> Result<Json> {
     let Some(sheet) = d.wb.active() else { return Err(EngineError::NoDocument) };
     let sel = &mut d.selection;
     // Extension moves the far corner, not the active cell.
-    let from = if extend {
-        let r = sel.current();
-        let far_row = if sel.anchor.row == r.start.row { r.end.row } else { r.start.row };
-        let far_col = if sel.anchor.col == r.start.col { r.end.col } else { r.start.col };
-        CellRef::new(far_row, far_col)
-    } else {
-        sel.active
-    };
+    let from = if extend { sel.moving_end() } else { sel.active };
     // Skip hidden rows/columns and step over merged areas.
     let mut to = if jmp {
         jump(sheet, from, dr.signum(), dc.signum())
@@ -1111,6 +1101,20 @@ fn paste_special(s: &mut Session, p: &Json) -> Result<Json> {
                                 }
                             }
                         }
+                        // The copied cell's validation rule replaces whatever rule the destination had.
+                        if !link && matches!(what, What::All | What::AllExceptBorders | What::Validation) {
+                            let rule = src_sheet.validations.iter().find(|dv| dv.ranges.iter().any(|r| r.contains(sc))).cloned();
+                            let sh = cx.sheet_mut(dest_sheet)?;
+                            super::data::remove_validation_cells(&mut sh.validations, &[RangeRef::new(dest, dest)]);
+                            if let Some(mut dv) = rule {
+                                // Relative references move with the rule, as pasted formulas do.
+                                let first = dv.ranges.first().map_or(sc, |r| r.start);
+                                dv.f1 = super::data::move_rule_formula(&dv.f1, first, dest);
+                                dv.f2 = dv.f2.map(|f| super::data::move_rule_formula(&f, first, dest));
+                                dv.ranges = vec![RangeRef::new(dest, dest)];
+                                sh.validations.push(dv);
+                            }
+                        }
                         match what {
                             What::Comments => {
                                 if let Some(cm) = src_sheet.comments.get(&sc).cloned() {
@@ -1583,6 +1587,23 @@ fn begin_edit(s: &mut Session, _: &Json) -> Result<Json> {
 mod tests {
     use super::*;
 
+    #[test]
+    fn cell_set_takes_numbers_for_input_and_value() {
+        // #697: a JSON number for `input` used to clear the cell instead of entering it.
+        let mut s = Session::new();
+        s.new_workbook();
+        s.execute("cell.set", json!({"cell": "A1", "input": 123.5})).unwrap();
+        s.execute("cell.set", json!({"cell": "A2", "value": 77})).unwrap();
+        s.execute("cell.set", json!({"cell": "A3", "input": true})).unwrap();
+        s.execute("cell.set", json!({"cell": "A4", "input": "=A1+A2"})).unwrap();
+        let get = |s: &mut Session, a: &str| s.execute("cell.get", json!({"cell": a})).unwrap();
+        assert_eq!(get(&mut s, "A1")["value"], json!(123.5));
+        assert_eq!(get(&mut s, "A2")["value"], json!(77.0));
+        assert_eq!(get(&mut s, "A3")["value"], json!(true));
+        assert_eq!(get(&mut s, "A4")["value"], json!(200.5));
+        assert!(s.execute("cell.set", json!({"cell": "A5"})).is_err());
+    }
+
     #[test]
     fn legacy_array_entry() {
         let mut s = Session::new();
diff --git a/crates/engine/src/cmd/extra.rs b/crates/engine/src/cmd/extra.rs
index a08f080..62bc515 100644
--- a/crates/engine/src/cmd/extra.rs
+++ b/crates/engine/src/cmd/extra.rs
@@ -701,6 +701,12 @@ fn stash_get(wb: &Workbook, key: &str) -> Json {
         .unwrap_or(json!({}))
 }
 
+/// Like `stash_get`, for the name-keyed lists (views, scripts): a stored value that is not a JSON object is treated as empty.
+fn stash_map(wb: &Workbook, key: &str) -> Json {
+    let v = stash_get(wb, key);
+    if v.is_object() { v } else { json!({}) }
+}
+
 fn stash_set(wb: &mut Workbook, key: &str, v: &Json) {
     let text = v.to_string();
     let formula = format!("\"{}\"", text.replace('"', "\"\""));
@@ -723,7 +729,7 @@ pub(crate) fn keep_watch_list(from: &Workbook, to: &mut std::sync::Arc<Workbook>
 
 fn custom_views(s: &mut Session, p: &Json) -> Result<Json> {
     let d = s.doc()?;
-    let mut views = stash_get(&d.wb, VIEWS_NAME);
+    let mut views = stash_map(&d.wb, VIEWS_NAME);
     if let Some(name) = str_param(p, "save") {
         let sh = d.wb.active().ok_or(EngineError::NoDocument)?;
         views[name] = json!({"sheet": d.wb.active_sheet, "selection": d.selection.a1(), "zoom": sh.zoom, "freeze": sh.freeze});
@@ -743,6 +749,17 @@ fn custom_views(s: &mut Session, p: &Json) -> Result<Json> {
         if let Some(z) = v["zoom"].as_u64() {
             s.execute("view.zoom", json!({"percent": z}))?;
         }
+        if let Some(f) = v.get("freeze") {
+            let freeze = match (f[0].as_u64(), f[1].as_u64()) {
+                (Some(r), Some(c)) => u32::try_from(r).ok().zip(u32::try_from(c).ok()),
+                _ => None,
+            };
+            edit(s, |cx| {
+                let si = cx.sheet_index();
+                cx.sheet_mut(si)?.freeze = freeze;
+                Ok(())
+            })?;
+        }
     } else if let Some(name) = str_param(p, "delete") {
         if let Some(o) = views.as_object_mut() {
             o.remove(name);
@@ -812,7 +829,7 @@ fn table_resize(s: &mut Session, p: &Json) -> Result<Json> {
         let sheet = cx.sheet_mut(si)?;
         let headers: Vec<String> = (r.start.col..=r.end.col).map(|c| sheet.value(CellRef::new(r.start.row, c)).display()).collect();
         let t = sheet.tables.get_mut(ti).ok_or_else(|| bad("table", "gone"))?;
-        if r.start.row != t.range.start.row {
+        if r.start.row != t.range.start.row || !r.intersects(&t.range) {
             return Err(EngineError::Other(
                 "The headers must remain in the same row, and the resulting table range must overlap the original table range.".into(),
             ));
@@ -938,7 +955,7 @@ fn new_script(s: &mut Session, p: &Json) -> Result<Json> {
         return Err(bad("automate.newScript", "`commands` must be an array"));
     }
     edit(s, |cx| {
-        let mut all = stash_get(&cx.wb, SCRIPTS_NAME);
+        let mut all = stash_map(&cx.wb, SCRIPTS_NAME);
         all[name.as_str()] = cmds.clone();
         stash_set(&mut cx.wb, SCRIPTS_NAME, &all);
         Ok(json!({"name": name}))
@@ -977,7 +994,7 @@ fn run_script(s: &mut Session, p: &Json) -> Result<Json> {
 fn delete_script(s: &mut Session, p: &Json) -> Result<Json> {
     let name = str_param(p, "name").ok_or_else(|| bad("automate.deleteScript", "missing `name`"))?.to_string();
     edit(s, |cx| {
-        let mut all = stash_get(&cx.wb, SCRIPTS_NAME);
+        let mut all = stash_map(&cx.wb, SCRIPTS_NAME);
         if let Some(o) = all.as_object_mut() {
             o.remove(&name);
         }
@@ -1052,8 +1069,13 @@ fn toggle_checkbox(s: &mut Session, p: &Json) -> Result<Json> {
     })
 }
 
+/// Copy of the params that is always a JSON object, so keys can be assigned; any other JSON value counts as no params (like null).
+fn object_params(p: &Json) -> Json {
+    Json::Object(p.as_object().cloned().unwrap_or_default())
+}
+
 fn theme_colors(s: &mut Session, p: &Json) -> Result<Json> {
-    let mut params = p.clone();
+    let mut params = object_params(p);
     if params.get("name").is_none() {
         params["name"] = json!(s.doc()?.wb.theme.name.clone());
     }
@@ -1074,7 +1096,7 @@ fn background(s: &mut Session, p: &Json) -> Result<Json> {
             Ok(Json::Null)
         });
     }
-    let mut params = p.clone();
+    let mut params = object_params(p);
     params["alt"] = json!("Sheet background");
     params["at"] = json!("A1");
     s.execute("insert.picture", params)
@@ -1090,7 +1112,7 @@ fn draw_border(s: &mut Session, p: &Json) -> Result<Json> {
         "outline" => "outside",
         _ => "all",
     };
-    let mut params = p.clone();
+    let mut params = object_params(p);
     params["preset"] = json!(preset);
     s.execute("home.borders", params)
 }
diff --git a/crates/engine/src/cmd/file.rs b/crates/engine/src/cmd/file.rs
index 3c4a101..2a8b435 100644
--- a/crates/engine/src/cmd/file.rs
+++ b/crates/engine/src/cmd/file.rs
@@ -75,7 +75,11 @@ fn open(s: &mut Session, p: &Json) -> Result<Json> {
     {
         s.close_document(0);
     }
-    let i = s.add_document(DocState::new(wb, path, title));
+    let mut doc = DocState::new(wb, path, title);
+    if crate::io::FileKind::from_path(&name).is_none() && gridcraft_xlsx::sniff(&bytes) == gridcraft_xlsx::Format::Xlsx {
+        doc.content_kind = Some(crate::io::FileKind::Xlsx);
+    }
+    let i = s.add_document(doc);
     // The decrypted-workbook notice is for the info bar, not a message box.
     let shown: Vec<&str> = warnings.iter().map(String::as_str).filter(|w| *w != crate::io::DECRYPTED_NOTICE).collect();
     if !shown.is_empty() {
@@ -105,11 +109,16 @@ fn save(s: &mut Session, p: &Json) -> Result<Json> {
         return super::print::export_pdf(s, &json!({"path": path}));
     }
     let d = s.doc_mut()?;
-    let bytes = crate::io::save_bytes(&d.wb, &path)?;
+    // The document's own file keeps the format its content had when opened; any other path
+    // goes by its extension.
+    let kind = crate::io::FileKind::from_path(&path).or(d.content_kind.filter(|_| d.path.as_deref() == Some(path.as_str())));
+    let bytes = match kind {
+        Some(kind) => crate::io::save_bytes_as(&d.wb, &path, kind)?,
+        None => crate::io::save_bytes(&d.wb, &path)?,
+    };
     crate::io::write_file(&path, &bytes)?;
-    let kind = crate::io::FileKind::from_path(&path).unwrap_or(crate::io::FileKind::Xlsx);
     // Only a full-fidelity format clears the dirty flag and becomes the document's file.
-    if matches!(kind, crate::io::FileKind::Xlsx | crate::io::FileKind::Json) {
+    if matches!(kind, Some(crate::io::FileKind::Xlsx | crate::io::FileKind::Json)) {
         d.saved = d.wb.clone();
         d.path = Some(path.clone());
     }
diff --git a/crates/engine/src/cmd/forecast.rs b/crates/engine/src/cmd/forecast.rs
index 13c120c..9795ea6 100644
--- a/crates/engine/src/cmd/forecast.rs
+++ b/crates/engine/src/cmd/forecast.rs
@@ -42,7 +42,7 @@ pub fn specs() -> Vec<CommandSpec> {
         "Forecast Sheet",
         ["Data", "Forecast"],
         None,
-        "{timeline?: \"A2:A25\", values?: \"B2:B25\" (default: the first two columns of `range`, the selection or the current region; a text first cell is the header), end?: timeline value or date text | periods?: n (default: a third of the history, at least 1; ≤10,000 and history × periods ≤ 500,000; history ≤ 10,000 rows), confidenceInterval?: bool (default true), confidence?: 0.95 or 95, seasonality?: \"auto\" | 0 (none) | 2–8,760, fillMissing?: interpolate|zeros, aggregate?: average|count|counta|max|median|min|sum, statistics?: bool, chart?: line|column} → {sheet, table, chart, history, periods}. Inserts a sheet before the active one: timeline, values, Forecast (FORECAST.ETS), Lower/Upper Confidence Bound (FORECAST.ETS.CONFINT), optional FORECAST.ETS.STAT table, and a chart.",
+        "{timeline?: \"A2:A25\", values?: \"B2:B25\" (default: the first two columns of `range`, the selection or the current region; a text first cell is the header), end?: timeline value or date text | periods?: n (default: a third of the history, at least 1; ≤10,000 and history × periods ≤ 500,000; history ≤ 10,000 rows), forecastStart?: a timeline value or date text on the history, before its last point (hindcast: the model is fit to the points before it, the forecast columns start there and run over the actuals; default and the last point: forecast after the history), confidenceInterval?: bool (default true), confidence?: 0.95 or 95, seasonality?: \"auto\" | 0 (none) | 2–8,760, fillMissing?: interpolate|zeros, aggregate?: average|count|counta|max|median|min|sum, statistics?: bool, chart?: line|column} → {sheet, table, chart, history, periods}. Inserts a sheet before the active one: timeline, values, Forecast (FORECAST.ETS), Lower/Upper Confidence Bound (FORECAST.ETS.CONFINT), optional FORECAST.ETS.STAT table, and a chart.",
         has_doc,
         forecast_sheet
     )]
@@ -223,13 +223,39 @@ fn forecast_sheet(s: &mut Session, p: &Json) -> Result<Json> {
     if !rows.iter().any(|r| matches!(r.1, Value::Number(_))) {
         return Err(EngineError::Other("There are no values to forecast.".into()));
     }
-    let end = match p.get("end") {
-        Some(Json::Number(n)) => n.as_f64(),
-        Some(Json::String(t)) if !t.trim().is_empty() => match gridcraft_core::parse::parse_input(t.trim(), sys).value {
-            Value::Number(end) => Some(end),
-            _ => return Err(bad(CMD, format!("`end` is not a number or a date: `{t}`"))),
-        },
-        _ => None,
+    let time_param = |key: &str| -> Result<Option<f64>> {
+        match p.get(key) {
+            Some(Json::Number(n)) => Ok(n.as_f64()),
+            Some(Json::String(t)) if !t.trim().is_empty() => match gridcraft_core::parse::parse_input(t.trim(), sys).value {
+                Value::Number(x) => Ok(Some(x)),
+                _ => Err(bad(CMD, format!("`{key}` is not a number or a date: `{t}`"))),
+            },
+            None | Some(Json::Null) => Ok(None),
+            Some(Json::String(_)) => Ok(None),
+            Some(_) => Err(bad(CMD, format!("`{key}` is not a number or a date"))),
+        }
+    };
+    let end = time_param("end")?;
+    // Forecast Start: the index (into `rows`) of the first forecast point, or `rows.len()` for the
+    // usual forecast after the history.
+    let fit = match time_param("forecastStart")? {
+        None => rows.len(),
+        Some(start) => {
+            let last_t = times.last().copied().unwrap_or(f64::NAN);
+            let tol = |a: f64, b: f64| (a - b).abs() <= 1e-9 * a.abs().max(b.abs()).max(1.0);
+            if tol(start, last_t) || timeline.after_last(1).is_some_and(|next| tol(start, next)) {
+                rows.len()
+            } else {
+                let i = times
+                    .iter()
+                    .position(|t| tol(*t, start))
+                    .ok_or_else(|| bad(CMD, "`forecastStart` is not on the timeline (it is a point of the history, before its last point)"))?;
+                if rows.get(..i).is_none_or(|h| h.iter().filter(|r| matches!(r.1, Value::Number(_))).count() < 2) {
+                    return Err(EngineError::Other("The forecast start needs at least two values before it to fit the forecast.".into()));
+                }
+                i
+            }
+        }
     };
     let cap = max_periods(rows.len());
     let periods = match end {
@@ -252,8 +278,9 @@ fn forecast_sheet(s: &mut Session, p: &Json) -> Result<Json> {
     // Columns: A timeline, B values, C forecast, D/E bounds.
     let n = rows.len() as u32;
     let last = n + 1; // 1-based row of the last history point
+    let fit_last = fit as u32 + 1; // 1-based row of the last point the model is fit to
     let end_row = last + periods; // 1-based row of the last forecast
-    let hist = |col: u32| format!("${0}$2:${0}${last}", col_letters(col));
+    let hist = |col: u32| format!("${0}$2:${0}${fit_last}", col_letters(col));
     let mut tail = format!("{},{}", opts.seasonality, opts.fill);
     if let Some(a) = opts.aggregate {
         tail.push_str(&format!(",{a}"));
@@ -305,22 +332,30 @@ fn forecast_sheet(s: &mut Session, p: &Json) -> Result<Json> {
                 put(&mut sheet, r, 1, v.clone(), vstyle);
             }
         }
-        // The last history point starts the forecast lines, so they join the values.
-        formula(&mut sheet, n, 2, format!("=B{last}"), vstyle);
+        // The last point the model is fit to starts the forecast lines, so they join the values.
+        let join = fit_last - 1; // 0-based row
+        formula(&mut sheet, join, 2, format!("=B{fit_last}"), vstyle);
         if opts.confidence.is_some() {
-            formula(&mut sheet, n, 3, format!("=C{last}"), vstyle);
-            formula(&mut sheet, n, 4, format!("=C{last}"), vstyle);
+            formula(&mut sheet, join, 3, format!("=C{fit_last}"), vstyle);
+            formula(&mut sheet, join, 4, format!("=C{fit_last}"), vstyle);
         }
         let (tl, vl) = (hist(0), hist(1));
+        let forecast_row = |sheet: &mut Sheet, r: u32| {
+            formula(sheet, r - 1, 2, format!("=FORECAST.ETS(A{r},{vl},{tl},{tail})"), vstyle);
+            if let Some(c) = opts.confidence {
+                let ci = format!("FORECAST.ETS.CONFINT(A{r},{vl},{tl},{c},{tail})");
+                formula(sheet, r - 1, 3, format!("=C{r}-{ci}"), vstyle);
+                formula(sheet, r - 1, 4, format!("=C{r}+{ci}"), vstyle);
+            }
+        };
+        // Hindcast: forecasts over the actuals from the start to the last history point.
+        for r in (fit_last + 1)..=last {
+            forecast_row(&mut sheet, r);
+        }
         for (k, t) in future.iter().enumerate() {
             let r = last + k as u32 + 1; // 1-based
             put(&mut sheet, r - 1, 0, Value::Number(*t), tstyle);
-            formula(&mut sheet, r - 1, 2, format!("=FORECAST.ETS(A{r},{vl},{tl},{tail})"), vstyle);
-            if let Some(c) = opts.confidence {
-                let ci = format!("FORECAST.ETS.CONFINT(A{r},{vl},{tl},{c},{tail})");
-                formula(&mut sheet, r - 1, 3, format!("=C{r}-{ci}"), vstyle);
-                formula(&mut sheet, r - 1, 4, format!("=C{r}+{ci}"), vstyle);
-            }
+            forecast_row(&mut sheet, r);
         }
         if opts.statistics {
             put(&mut sheet, 0, stats_col, Value::text("Statistic"), bold);
@@ -407,7 +442,7 @@ fn forecast_sheet(s: &mut Session, p: &Json) -> Result<Json> {
     if let Ok(d) = s.doc_mut() {
         d.sheet_selections.insert(index.min(d.sheet_selections.len()), crate::Selection::default());
     }
-    Ok(json!({"sheet": sheet_name, "table": table_name, "chart": chart_id, "history": n, "periods": periods}))
+    Ok(json!({"sheet": sheet_name, "table": table_name, "chart": chart_id, "history": n, "periods": periods, "fitted": fit}))
 }
 
 /// Forecast rows needed to reach `end` (rounded up to whole steps).
@@ -545,4 +580,39 @@ mod tests {
         s.execute("cell.set", json!({"cell": "A5", "input": "4.5"})).unwrap();
         assert!(s.execute("data.forecastSheet", json!({"range": "Sheet1!A1:B17"})).is_err());
     }
+
+    #[test]
+    fn forecast_start_hindcasts_over_the_actuals() {
+        let mut s = session_with_history(); // t = 1..16 in A2:A17
+        let r = s.execute("data.forecastSheet", json!({"range": "A1:B17", "forecastStart": 13, "periods": 2, "confidenceInterval": false})).unwrap();
+        assert_eq!(r["fitted"], 12);
+        // Fit to t = 1..12 (rows 2..13); the line joins at row 13 and forecasts rows 14..19.
+        assert_eq!(formula(&s, 0, "C13"), "B13");
+        assert_eq!(value(&s, 0, "C13"), value(&s, 0, "B13"));
+        assert_eq!(formula(&s, 0, "C14"), "FORECAST.ETS(A14,$B$2:$B$13,$A$2:$A$13,1,1)");
+        assert_eq!(formula(&s, 0, "C19"), "FORECAST.ETS(A19,$B$2:$B$13,$A$2:$A$13,1,1)");
+        // The exact seasonal series is recovered, and the actual is still shown next to it.
+        let c14 = value(&s, 0, "C14").as_f64().unwrap();
+        assert!((c14 - 39.0).abs() < 1e-6, "{c14}"); // t = 13: 10 + 26 + 3
+        assert!(value(&s, 0, "B14").as_f64().is_some());
+        // Start at the last point or one step later: as without forecastStart.
+        for start in [json!(16), json!(17)] {
+            let r = s.execute("data.forecastSheet", json!({"range": "Sheet1!A1:B17", "forecastStart": start, "periods": 2})).unwrap();
+            assert_eq!(r["fitted"], 16);
+        }
+        assert_eq!(formula(&s, 0, "C18"), "FORECAST.ETS(A18,$B$2:$B$17,$A$2:$A$17,1,1)");
+    }
+
+    #[test]
+    fn forecast_start_invalid_values_are_errors() {
+        let mut s = session_with_history();
+        let sheets = s.doc().unwrap().wb.sheets.len();
+        for bad in [json!(0), json!(2), json!(3.5), json!(18), json!(1000), json!("abc"), json!([1]), json!(1e308)] {
+            assert!(s.execute("data.forecastSheet", json!({"range": "A1:B17", "forecastStart": bad})).is_err(), "{bad}");
+        }
+        assert_eq!(s.doc().unwrap().wb.sheets.len(), sheets);
+        // Blank or null behaves like no start; empty params unchanged.
+        let r = s.execute("data.forecastSheet", json!({"range": "A1:B17", "forecastStart": ""})).unwrap();
+        assert_eq!(r["fitted"], 16);
+    }
 }
diff --git a/crates/engine/src/cmd/format.rs b/crates/engine/src/cmd/format.rs
index dde5fa1..3ed8ac1 100644
--- a/crates/engine/src/cmd/format.rs
+++ b/crates/engine/src/cmd/format.rs
@@ -574,6 +574,16 @@ fn merge(s: &mut Session, p: &Json, how: &str) -> Result<Json> {
                         let m = RangeRef::new(CellRef::new(row, r.start.col), CellRef::new(row, r.end.col));
                         if !m.is_single() {
                             sh.merges.push(m);
+                            // As below: only the first value of each row survives.
+                            let others: Vec<CellRef> = sh.cells.iter_range(m).map(|(c, _)| c).filter(|c| *c != m.start).collect();
+                            for c in others {
+                                if let Some(mut cell) = sh.cells.get(c).cloned() {
+                                    cell.value = gridcraft_core::Value::Empty;
+                                    cell.formula = None;
+                                    sh.set_cell(c, cell);
+                                }
+                                touched.push((sheet, c));
+                            }
                         }
                     }
                 }
@@ -953,6 +963,7 @@ fn row_height(s: &mut Session, p: &Json) -> Result<Json> {
                 e.custom = true;
             }
         }
+        cx.structural = true; // setting a height shows or hides rows: SUBTOTAL(10x) depends on it
         Ok(Json::Null)
     })
 }
@@ -992,9 +1003,7 @@ pub fn chars_to_points(c: f64) -> f64 {
     }
 }
 
-pub fn points_to_chars(px: f64) -> f64 {
-    if px <= 12.0 { (px / 12.0 * 100.0).round() / 100.0 } else { ((px - 5.0) / 7.0 * 100.0 + 0.5).trunc() / 100.0 }
-}
+pub use gridcraft_model::points_to_chars;
 
 /// Approximate text width in points for autofit (no font metrics in the engine: average glyph
 /// widths for the default font; the UI refines with real measurement when it autofits).
@@ -1069,6 +1078,7 @@ fn autofit_rows(s: &mut Session, p: &Json) -> Result<Json> {
             }
             cx.fit_rows.extend((a..=b).map(|r| (si, r)));
         }
+        cx.structural = true; // autofit reveals hidden rows: SUBTOTAL(10x) depends on it
         Ok(Json::Null)
     })
 }
@@ -1112,6 +1122,19 @@ fn hide(s: &mut Session, p: &Json, rows: bool, on: bool) -> Result<Json> {
 mod tests {
     use super::*;
 
+    #[test]
+    fn merge_across_keeps_the_first_value_of_each_row() {
+        let mut s = crate::Session::new();
+        s.new_workbook();
+        s.execute("range.setValues", json!({"range": "A1", "values": [[1, 2], [3, 4]]})).unwrap();
+        s.execute("cell.set", json!({"cell": "D1", "input": "=SUM(A1:B2)"})).unwrap();
+        s.execute("home.mergeAcross", json!({"range": "A1:B2"})).unwrap();
+        let v = |s: &mut crate::Session, a: &str| s.execute("cell.get", json!({"cell": a})).unwrap()["value"].clone();
+        assert_eq!(v(&mut s, "B1"), Json::Null);
+        assert_eq!(v(&mut s, "B2"), Json::Null);
+        assert_eq!(v(&mut s, "D1"), json!(4.0));
+    }
+
     #[test]
     fn decimal_steps() {
         let v = gridcraft_core::Value::Number(1.5);
diff --git a/crates/engine/src/cmd/insert.rs b/crates/engine/src/cmd/insert.rs
index 392c5ee..e589e60 100644
--- a/crates/engine/src/cmd/insert.rs
+++ b/crates/engine/src/cmd/insert.rs
@@ -153,7 +153,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Link",
             ["Insert", "Links"],
             Some("Cmd+K"),
-            "{cell?, target: \"https://…\" | \"Sheet2!A1\" | \"mailto:…\", text?, tooltip?, remove?: bool}",
+            "{cell?, target: \"https://…\" | \"Book.xlsx\" | \"Sheet2!A1\" | \"mailto:…\", text?, tooltip?, remove?: bool}",
             has_doc,
             insert_link
         ),
@@ -240,7 +240,7 @@ fn insert_table(s: &mut Session, p: &Json) -> Result<Json> {
     let name = str_param(p, "name")
         .map(str::to_string)
         .unwrap_or_else(|| (1..).map(|n| format!("Table{n}")).find(|n| d.wb.table(n).is_none()).unwrap_or_else(|| "Table".into()));
-    if name.is_empty() || name.contains(' ') || name.chars().next().is_some_and(|c| c.is_ascii_digit()) || CellRef::parse(&name).is_some() {
+    if !valid_table_name(&name) {
         return Err(EngineError::Other("The name that you entered is not valid.".into()));
     }
     if d.wb.table(&name).is_some() || d.wb.names.iter().any(|n| n.name.eq_ignore_ascii_case(&name)) {
@@ -349,6 +349,9 @@ fn table_flag(s: &mut Session, p: &Json, which: &str) -> Result<Json> {
             "totals" => {
                 let v = on.unwrap_or(!t.totals_row);
                 if v != t.totals_row {
+                    if v && t.range.end.row.saturating_add(1) >= MAX_ROWS {
+                        return Err(EngineError::Other("There's no room below the table for the total row.".into()));
+                    }
                     t.totals_row = v;
                     if v {
                         t.range.end.row += 1;
@@ -448,14 +451,19 @@ fn table_style(s: &mut Session, p: &Json) -> Result<Json> {
     })
 }
 
+/// Table names follow the Microsoft name rules, as the xlsx writer does: letters, digits, `_` and `.`,
+/// starting with a letter, `_` or `\`. Anything else (a hyphen, say) would read as an operator inside a
+/// structured reference, and the writer would rename the table on save.
+fn valid_table_name(name: &str) -> bool {
+    name.starts_with(|c: char| c.is_alphabetic() || c == '_' || c == '\\')
+        && CellRef::parse(name).is_none()
+        && name.chars().enumerate().all(|(i, c)| c.is_alphanumeric() || c == '_' || c == '.' || (i == 0 && c == '\\'))
+}
+
 fn table_rename(s: &mut Session, p: &Json) -> Result<Json> {
     let (si, ti) = find_table(s, p)?;
     let name = str_param(p, "name").ok_or_else(|| bad("table.rename", "missing `name`"))?.to_string();
-    if name.is_empty()
-        || name.contains(' ')
-        || name.chars().next().is_some_and(|c| c.is_ascii_digit())
-        || gridcraft_core::CellRef::parse(&name).is_some()
-    {
+    if !valid_table_name(&name) {
         return Err(EngineError::Other("The name that you entered is not valid.".into()));
     }
     if s.doc()?.wb.table(&name).is_some_and(|x| x != (si, ti)) {
@@ -470,6 +478,8 @@ fn table_rename(s: &mut Session, p: &Json) -> Result<Json> {
         for i in 0..cx.wb.sheets.len() {
             let keys: Vec<(CellRef, std::sync::Arc<Formula>)> =
                 cx.wb.sheets.get(i).map(|s| s.cells.iter().filter_map(|(c, x)| x.formula.clone().map(|f| (c, f))).collect()).unwrap_or_default();
+            // A bare name that is also a defined name resolves to the defined name, so it is not the table.
+            let shadowed = cx.wb.name(&old, i).is_some();
             let Some(sh) = cx.wb.sheet_mut(i) else { continue };
             for (c, f) in keys {
                 let Some(e) = f.expr() else { continue };
@@ -478,7 +488,7 @@ fn table_rename(s: &mut Session, p: &Json) -> Result<Json> {
                         st.table = name.clone();
                         gridcraft_formula::Expr::Struct(st)
                     }
-                    gridcraft_formula::Expr::Name(n) if n.eq_ignore_ascii_case(&old) => gridcraft_formula::Expr::Name(name.clone()),
+                    gridcraft_formula::Expr::Name(n) if !shadowed && n.eq_ignore_ascii_case(&old) => gridcraft_formula::Expr::Name(name.clone()),
                     o => o,
                 });
                 if let Some(cell) = sh.cells.get_mut(c) {
@@ -1156,6 +1166,7 @@ fn insert_link(s: &mut Session, p: &Json) -> Result<Json> {
     };
     let text = str_param(p, "text").map(str::to_string);
     let tooltip = str_param(p, "tooltip").map(str::to_string);
+    let external = links_outside(&s.doc()?.wb, sheet, &target);
     edit(s, |cx| {
         let link_style = cx.wb.styles.derive(cx.wb.sheet(sheet).map(|sh| sh.style_id(at)).unwrap_or_default(), |st| {
             st.font.color = Color::Theme(10, 0);
@@ -1167,12 +1178,30 @@ fn insert_link(s: &mut Session, p: &Json) -> Result<Json> {
         } else {
             sh.set_style(at, link_style);
         }
-        sh.hyperlinks.insert(at, Hyperlink { target: target.clone(), tooltip: tooltip.clone() });
+        sh.hyperlinks.insert(at, Hyperlink { target: target.clone(), tooltip: tooltip.clone(), external });
         cx.touch(sheet, at);
         Ok(Json::Null)
     })
 }
 
+/// Sorts a link target as the two pages of Excel's Insert Hyperlink dialog do: "Place in This
+/// Document" is a sheet reference, a defined name or `#…`; anything else ("Existing File or Web
+/// Page") is outside the workbook and saved as a relationship.
+fn links_outside(wb: &Workbook, sheet: usize, target: &str) -> bool {
+    let t = target.trim();
+    if t.starts_with('#') || wb.name(t, sheet).is_some() || wb.table(t).is_some() {
+        return false;
+    }
+    let (on, body) = split_sheet(t);
+    // Sheet names can't hold `: \ / ? * [ ]`, so `https://…!A1` or `C:\…!A1` is no sheet reference,
+    // and `Book.xlsx#Sheet1!A1` is a place in another file unless a sheet has that name.
+    let on_sheet = on.is_none_or(|name| {
+        wb.sheets.iter().any(|s| s.name.eq_ignore_ascii_case(&name))
+            || (!name.is_empty() && !name.contains([':', '\\', '/', '?', '*', '[', ']', '#']))
+    });
+    !(on_sheet && RangeRef::parse(body).is_some())
+}
+
 fn comment(s: &mut Session, p: &Json, threaded: bool) -> Result<Json> {
     let sheet = target_sheet(s, p)?;
     let at = cell_param_on(s, p, "cell", sheet)?.unwrap_or(s.doc()?.selection.active);
@@ -1420,20 +1449,20 @@ fn manage_cf(s: &mut Session, p: &Json) -> Result<Json> {
     }
     edit(s, |cx| {
         let sh = cx.sheet_mut(sheet)?;
-        let n = sh.cond_formats.len();
+        // The count is taken again after each step: a delete shortens the list.
         if let Some(i) = u32_param(p, "delete").map(|v| v as usize)
-            && i < n
+            && i < sh.cond_formats.len()
         {
             sh.cond_formats.remove(i);
         }
         if let Some(i) = u32_param(p, "moveUp").map(|v| v as usize)
             && i > 0
-            && i < n
+            && i < sh.cond_formats.len()
         {
             sh.cond_formats.swap(i, i - 1);
         }
         if let Some(i) = u32_param(p, "moveDown").map(|v| v as usize)
-            && i + 1 < n
+            && i + 1 < sh.cond_formats.len()
         {
             sh.cond_formats.swap(i, i + 1);
         }
@@ -1466,3 +1495,23 @@ fn insert_icon(s: &mut Session, p: &Json) -> Result<Json> {
         Ok(json!({"shape": id}))
     })
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn manage_rules_delete_then_move() {
+        let mut s = Session::new();
+        s.new_workbook();
+        for v in ["1", "2"] {
+            let rule = json!({"type": "cellIs", "operator": "greaterThan", "value": v, "preset": "lightRedFill"});
+            s.execute("home.conditionalFormat", json!({"range": "A1:A3", "rule": rule})).unwrap();
+        }
+        // Deleting first left two rules' worth of indices for the move: it panicked.
+        s.execute("home.manageRules", json!({"delete": 0, "moveUp": 1})).unwrap();
+        s.execute("home.manageRules", json!({"delete": 0, "moveDown": 0})).unwrap();
+        let rules = s.execute("home.manageRules", json!({})).unwrap();
+        assert_eq!(rules["rules"].as_array().map(Vec::len), Some(0));
+    }
+}
diff --git a/crates/engine/src/cmd/pivot.rs b/crates/engine/src/cmd/pivot.rs
index 0d73b0a..8a441fa 100644
--- a/crates/engine/src/cmd/pivot.rs
+++ b/crates/engine/src/cmd/pivot.rs
@@ -87,7 +87,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Move Field",
             [],
             None,
-            "{pivot?, field, from: rows|columns|values|filters, to: rows|columns|values|filters, position?: index, replace?}",
+            "{pivot?, field (\"Σ Values\" moves the value fields between rows and columns; in columns it stays after the last field), from: rows|columns|values|filters, to: rows|columns|values|filters, position?: index, replace?}",
             has_doc,
             move_field
         ),
@@ -333,6 +333,71 @@ fn in_axes(pt: &PivotTable, field: &str) -> bool {
     pt.rows.iter().chain(pt.columns.iter()).any(|f| f.source_col.eq_ignore_ascii_case(field))
 }
 
+/// Name of the Σ Values pseudo-field (where the value fields sit when there are two or more).
+const VALUES_FIELD: &str = "Σ Values";
+
+/// Whether `field` names Σ Values: `Σ Values`, or `Values` unless a source field has that name.
+fn is_values_field(src: &pv::Source, field: &str) -> bool {
+    let f = field.trim();
+    f == VALUES_FIELD || (f.eq_ignore_ascii_case("values") && src.col(f).is_none())
+}
+
+/// Keeps Σ Values in place after a field left (`inserted` false) or arrived at index `i` of
+/// Rows (`rows`) or Columns.
+fn shift_values(pt: &mut PivotTable, rows: bool, i: usize, inserted: bool) {
+    if pt.values_on_rows != rows {
+        return;
+    }
+    let Some(p) = pt.values_position else { return };
+    // Σ Values stays just ahead of the field it preceded.
+    let p = match inserted {
+        true if i <= p => p + 1,
+        false if i < p => p - 1,
+        _ => p,
+    };
+    let n = if rows { pt.rows.len() } else { pt.columns.len() };
+    pt.values_position = (p < n).then_some(p);
+}
+
+/// Takes `field` out of Rows and Columns (Σ Values keeps its place); returns its first entry.
+fn take_from_axes(pt: &mut PivotTable, field: &str) -> Option<PivotField> {
+    let mut first = None;
+    for rows in [true, false] {
+        loop {
+            let list = if rows { &mut pt.rows } else { &mut pt.columns };
+            let Some(i) = list.iter().position(|f| f.source_col.eq_ignore_ascii_case(field)) else { break };
+            let f = list.remove(i);
+            shift_values(pt, rows, i, false);
+            first.get_or_insert(f);
+        }
+    }
+    first
+}
+
+/// Inserts `f` into Rows (`rows`) or Columns at `position` (default: the end).
+fn insert_axis_field(pt: &mut PivotTable, rows: bool, f: PivotField, position: Option<usize>) {
+    let list = if rows { &mut pt.rows } else { &mut pt.columns };
+    let at = position.unwrap_or(list.len()).min(list.len());
+    list.insert(at, f);
+    shift_values(pt, rows, at, true);
+}
+
+/// Moves Σ Values between Rows and Columns, or within Rows, to `position` (default: the end).
+/// In Columns it always comes after the last column field: the column layout doesn't place it
+/// anywhere else yet.
+fn move_values_field(cmd: &str, pt: &mut PivotTable, from: &str, to: &str, position: Option<usize>) -> Result<Json> {
+    let current = if pt.values_on_rows { "rows" } else { "columns" };
+    if from != current {
+        return Err(bad(cmd, format!("`{VALUES_FIELD}` isn't in the {from} area")));
+    }
+    if !matches!(to, "rows" | "columns") {
+        return Err(other("The field you are moving cannot be placed in that PivotTable area."));
+    }
+    pt.values_on_rows = to == "rows";
+    pt.values_position = position.filter(|p| pt.values_on_rows && *p < pt.rows.len());
+    Ok(json!({"field": VALUES_FIELD, "to": to}))
+}
+
 /// The canonical source field name for `field`.
 fn canonical(cmd: &str, src: &pv::Source, field: &str) -> Result<String> {
     src.col(field).and_then(|c| src.headers.get(c).cloned()).ok_or_else(|| bad(cmd, format!("no field `{field}` in the source data")))
@@ -384,21 +449,11 @@ fn add_to_area(
             if pt.rows.len() + pt.columns.len() >= pv::MAX_AXIS_FIELDS && !in_axes(pt, &field) {
                 return Err(other(format!("A PivotTable can have at most {} row and column fields.", pv::MAX_AXIS_FIELDS)));
             }
-            let existing = pt
-                .rows
-                .iter()
-                .chain(pt.columns.iter())
-                .find(|f| f.source_col.eq_ignore_ascii_case(&field))
-                .cloned()
-                .unwrap_or_else(|| PivotField { source_col: field.clone(), ..Default::default() });
-            pt.rows.retain(|f| !f.source_col.eq_ignore_ascii_case(&field));
-            pt.columns.retain(|f| !f.source_col.eq_ignore_ascii_case(&field));
+            let existing = take_from_axes(pt, &field).unwrap_or_else(|| PivotField { source_col: field.clone(), ..Default::default() });
             // A report filter that selects nothing in particular goes away; a selection stays
             // as the field's hidden items.
             pt.filters.retain(|f| !(f.source_col.eq_ignore_ascii_case(&field) && f.selected.is_none()));
-            let list = if area == "rows" { &mut pt.rows } else { &mut pt.columns };
-            let at = position.unwrap_or(list.len()).min(list.len());
-            list.insert(at, existing);
+            insert_axis_field(pt, area == "rows", existing, position);
         }
         "values" => {
             if pt.values.len() >= pv::MAX_VALUE_FIELDS {
@@ -421,8 +476,7 @@ fn add_to_area(
             pt.values.insert(at, v);
         }
         _ => {
-            pt.rows.retain(|f| !f.source_col.eq_ignore_ascii_case(&field));
-            pt.columns.retain(|f| !f.source_col.eq_ignore_ascii_case(&field));
+            take_from_axes(pt, &field);
             let existing = pt.filters.iter().position(|f| f.source_col.eq_ignore_ascii_case(&field));
             let entry = match existing {
                 Some(i) => pt.filters.remove(i),
@@ -439,12 +493,14 @@ fn add_to_area(
 fn remove_from_area(cmd: &str, pt: &mut PivotTable, field: &str, area: &str) -> Result<String> {
     match area {
         "rows" | "columns" => {
-            let list = if area == "rows" { &mut pt.rows } else { &mut pt.columns };
+            let rows = area == "rows";
+            let list = if rows { &mut pt.rows } else { &mut pt.columns };
             let i = list
                 .iter()
                 .position(|f| f.source_col.eq_ignore_ascii_case(field))
                 .ok_or_else(|| bad(cmd, format!("`{field}` isn't in the {area} area")))?;
             let f = list.remove(i);
+            shift_values(pt, rows, i, false);
             pt.filters.retain(|x| !x.source_col.eq_ignore_ascii_case(&f.source_col));
             Ok(f.source_col)
         }
@@ -699,6 +755,8 @@ fn pivot_json(wb: &Workbook, si: usize, pt: &PivotTable) -> Json {
         "style": pt.style,
         "showHeaders": pt.show_headers,
         "calculatedFields": pt.calculated_fields.iter().map(|c| json!({"name": c.name, "formula": c.formula})).collect::<Vec<_>>(),
+        "valuesOnRows": pt.values_on_rows,
+        "valuesPosition": pt.values_position,
     })
 }
 
@@ -890,18 +948,22 @@ fn move_field(s: &mut Session, p: &Json) -> Result<Json> {
     let to = area_param(C, str_param(p, "to"))?;
     let pos = position_param(p);
     update(s, p, |pt, src, _| {
+        if is_values_field(src, &field) {
+            return move_values_field(C, pt, from, to, pos);
+        }
         if from == to {
             // Reorder within the area.
             match from {
                 "rows" | "columns" => {
-                    let list = if from == "rows" { &mut pt.rows } else { &mut pt.columns };
+                    let rows = from == "rows";
+                    let list = if rows { &mut pt.rows } else { &mut pt.columns };
                     let i = list
                         .iter()
                         .position(|f| f.source_col.eq_ignore_ascii_case(&field))
                         .ok_or_else(|| bad(C, format!("`{field}` isn't in the {from} area")))?;
                     let f = list.remove(i);
-                    let at = pos.unwrap_or(list.len()).min(list.len());
-                    list.insert(at, f);
+                    shift_values(pt, rows, i, false);
+                    insert_axis_field(pt, rows, f, pos);
                 }
                 "values" => {
                     let i = pt
@@ -1270,8 +1332,20 @@ fn change_source(s: &mut Session, p: &Json) -> Result<Json> {
             }
             ok
         };
-        pt.rows.retain(|f| keep(&f.source_col, &mut dropped));
-        pt.columns.retain(|f| keep(&f.source_col, &mut dropped));
+        // Axis fields leave one by one so Σ Values keeps its place among the rest.
+        for rows in [true, false] {
+            let mut i = 0;
+            loop {
+                let list = if rows { &mut pt.rows } else { &mut pt.columns };
+                let Some(f) = list.get(i) else { break };
+                if keep(&f.source_col, &mut dropped) {
+                    i += 1;
+                } else {
+                    list.remove(i);
+                    shift_values(pt, rows, i, false);
+                }
+            }
+        }
         pt.values.retain(|f| keep(&f.source_col, &mut dropped));
         pt.filters.retain(|f| keep(&f.source_col, &mut dropped));
         Ok(json!({"source": source, "dropped": dropped}))
@@ -1722,6 +1796,167 @@ mod tests {
         assert_eq!(text(&s, "A5"), "Apples");
     }
 
+    #[test]
+    fn values_on_rows_layouts() {
+        let mut s = sales();
+        s.execute("insert.pivotTable", json!({"rows": ["Region"], "values": ["Sales", "Units"]})).unwrap();
+        assert_eq!(text(&s, "C3"), "Sum of Units");
+        // Σ Values after Region: each region holds one line per value field.
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "rows"})).unwrap();
+        let p = pt(&s);
+        assert!(p.values_on_rows);
+        assert_eq!(p.values_position, None);
+        let r = p.last_range.unwrap();
+        assert_eq!(r.width(), 2);
+        // header + 3 × (region + 2 values) + 2 grand totals
+        assert_eq!(r.height(), 1 + 9 + 2);
+        assert_eq!(text(&s, "A4"), "East");
+        assert_eq!(val(&s, "B4"), Value::Empty);
+        assert_eq!(text(&s, "A5"), "Sum of Sales");
+        assert_eq!(val(&s, "B5"), Value::Number(415.0));
+        assert_eq!(text(&s, "A6"), "Sum of Units");
+        assert_eq!(val(&s, "B6"), Value::Number(33.0));
+        assert_eq!(text(&s, "A13"), "Total Sum of Sales");
+        assert_eq!(val(&s, "B13"), Value::Number(TOTAL));
+        assert_eq!(text(&s, "A14"), "Total Sum of Units");
+        assert_eq!(val(&s, "B14"), Value::Number(72.0));
+        // Tabular, no column field: "Total" heads the data column, as Excel saves it.
+        s.execute("pivot.layout", json!({"layout": "tabular"})).unwrap();
+        assert_eq!(text(&s, "A3"), "Region");
+        assert_eq!(text(&s, "B3"), "Values");
+        assert_eq!(text(&s, "C3"), "Total");
+        s.execute("pivot.layout", json!({"layout": "compact"})).unwrap();
+        // Σ Values before Region: the value fields are the outer items.
+        s.execute("pivot.moveField", json!({"field": "Values", "from": "rows", "to": "rows", "position": 0})).unwrap();
+        assert_eq!(pt(&s).values_position, Some(0));
+        assert_eq!(text(&s, "A4"), "Sum of Sales");
+        assert_eq!(val(&s, "B4"), Value::Empty);
+        assert_eq!(text(&s, "A5"), "East");
+        assert_eq!(val(&s, "B5"), Value::Number(415.0));
+        assert_eq!(text(&s, "A8"), "Sum of Units");
+        assert_eq!(text(&s, "A9"), "East");
+        assert_eq!(val(&s, "B9"), Value::Number(33.0));
+        assert_eq!(text(&s, "A12"), "Total Sum of Sales");
+        assert_eq!(val(&s, "B13"), Value::Number(72.0));
+        // Adding a row field in front keeps Σ Values ahead of Region.
+        s.execute("pivot.addField", json!({"field": "Product", "area": "rows", "position": 0})).unwrap();
+        assert_eq!(pt(&s).values_position, Some(1));
+        s.execute("pivot.removeField", json!({"field": "Product", "area": "rows"})).unwrap();
+        assert_eq!(pt(&s).values_position, Some(0));
+        // No row field: one line per value field and no grand total.
+        s.execute("pivot.removeField", json!({"field": "Region", "area": "rows"})).unwrap();
+        let r = pt(&s).last_range.unwrap();
+        assert_eq!(r.height(), 1 + 2);
+        assert_eq!(text(&s, "A4"), "Sum of Sales");
+        assert_eq!(val(&s, "B4"), Value::Number(TOTAL));
+        assert_eq!(text(&s, "A5"), "Sum of Units");
+        assert_eq!(val(&s, "B5"), Value::Number(72.0));
+        // Back to Columns.
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "rows", "to": "columns"})).unwrap();
+        assert!(!pt(&s).values_on_rows);
+        assert_eq!(text(&s, "A3"), "Sum of Sales");
+        assert_eq!(text(&s, "B3"), "Sum of Units");
+        assert!(s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "filters"})).is_err());
+        assert!(s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "rows", "to": "columns"})).is_err());
+    }
+
+    #[test]
+    fn collapsed_item_puts_values_in_the_values_column() {
+        let mut s = sales();
+        s.execute("insert.pivotTable", json!({"rows": ["Region", "Product"], "values": ["Sales", "Units"]})).unwrap();
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "rows"})).unwrap();
+        s.execute("pivot.collapse", json!({"field": "Region", "items": ["East"]})).unwrap();
+        for layout in ["tabular", "outline"] {
+            s.execute("pivot.layout", json!({"layout": layout})).unwrap();
+            assert_eq!(text(&s, "C3"), "Values", "{layout}");
+            let east = (4..20).find(|r| text(&s, &format!("A{r}")) == "East").unwrap();
+            let first = if layout == "tabular" { east } else { east + 1 };
+            assert_eq!(text(&s, &format!("B{first}")), "", "{layout}");
+            assert_eq!(text(&s, &format!("C{first}")), "Sum of Sales", "{layout}");
+            assert_eq!(val(&s, &format!("D{first}")), Value::Number(415.0), "{layout}");
+            assert_eq!(text(&s, &format!("C{}", first + 1)), "Sum of Units", "{layout}");
+        }
+    }
+
+    #[test]
+    fn values_stay_last_in_columns() {
+        let mut s = sales();
+        s.execute("insert.pivotTable", json!({"rows": ["Product"], "columns": ["Region"], "values": ["Sales", "Units"]})).unwrap();
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "columns", "position": 0})).unwrap();
+        let p = pt(&s);
+        assert!(!p.values_on_rows);
+        assert_eq!(p.values_position, None);
+        // Σ Values to Rows and back with a position: still last in Columns.
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "rows"})).unwrap();
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "rows", "to": "columns", "position": 0})).unwrap();
+        assert_eq!(pt(&s).values_position, None);
+        assert_eq!(text(&s, "B5"), "Sum of Sales");
+        assert_eq!(text(&s, "C5"), "Sum of Units");
+    }
+
+    #[test]
+    fn change_source_keeps_values_ahead_of_its_field() {
+        let mut s = sales();
+        s.execute("insert.pivotTable", json!({"rows": ["Region", "Product"], "values": ["Sales", "Units"]})).unwrap();
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "rows", "position": 1})).unwrap();
+        // The new source has no Region: Σ Values stays ahead of Product.
+        s.execute("pivot.changeSource", json!({"source": "Sheet1!B1:E13"})).unwrap();
+        let p = pt(&s);
+        assert_eq!(p.rows.len(), 1);
+        assert_eq!(p.values_position, Some(0));
+        assert_eq!(text(&s, "A4"), "Sum of Sales");
+        assert_eq!(text(&s, "A5"), "Apples");
+    }
+
+    #[test]
+    fn values_on_rows_between_row_fields() {
+        let mut s = sales();
+        s.execute("insert.pivotTable", json!({"rows": ["Region", "Product"], "values": ["Sales", "Units"]})).unwrap();
+        s.execute("pivot.moveField", json!({"field": "Σ Values", "from": "columns", "to": "rows", "position": 1})).unwrap();
+        // Compact: East, then per value field its products, then per-value subtotals of East.
+        assert_eq!(text(&s, "A4"), "East");
+        assert_eq!(text(&s, "A5"), "Sum of Sales");
+        assert_eq!(text(&s, "A6"), "Apples");
+        assert_eq!(val(&s, "B6"), Value::Number(160.0));
+        assert_eq!(text(&s, "A9"), "Sum of Units");
+        assert_eq!(text(&s, "A10"), "Apples");
+        assert_eq!(val(&s, "B10"), Value::Number(16.0));
+        assert_eq!(text(&s, "A13"), "East Sum of Sales");
+        assert_eq!(val(&s, "B13"), Value::Number(415.0));
+        assert_eq!(text(&s, "A14"), "East Sum of Units");
+        assert_eq!(val(&s, "B14"), Value::Number(33.0));
+        let d = s.doc().unwrap();
+        let sh = d.wb.active().unwrap();
+        assert_eq!(d.wb.styles.get(sh.style_id(CellRef::parse("A5").unwrap())).align.indent, 1);
+        assert_eq!(d.wb.styles.get(sh.style_id(CellRef::parse("A6").unwrap())).align.indent, 2);
+        // Outline: one column per level, "Values" heads the Σ Values column.
+        s.execute("pivot.layout", json!({"layout": "outline"})).unwrap();
+        assert_eq!(pt(&s).last_range.unwrap().width(), 4);
+        assert_eq!(text(&s, "A3"), "Region");
+        assert_eq!(text(&s, "B3"), "Values");
+        assert_eq!(text(&s, "C3"), "Product");
+        assert_eq!(text(&s, "B5"), "Sum of Sales");
+        assert_eq!(text(&s, "C6"), "Apples");
+        assert_eq!(val(&s, "D6"), Value::Number(160.0));
+        // Tabular: labels start on their parent's row; totals per value field below each group.
+        s.execute("pivot.layout", json!({"layout": "tabular"})).unwrap();
+        assert_eq!(text(&s, "A4"), "East");
+        assert_eq!(text(&s, "B4"), "Sum of Sales");
+        assert_eq!(text(&s, "C4"), "Apples");
+        assert_eq!(val(&s, "D4"), Value::Number(160.0));
+        assert_eq!(text(&s, "B7"), "Sum of Units");
+        assert_eq!(text(&s, "C7"), "Apples");
+        assert_eq!(val(&s, "D7"), Value::Number(16.0));
+        assert_eq!(text(&s, "A10"), "East Sum of Sales");
+        assert_eq!(val(&s, "D10"), Value::Number(415.0));
+        assert_eq!(text(&s, "A11"), "East Sum of Units");
+        let r = pt(&s).last_range.unwrap();
+        let last = r.end.row + 1;
+        assert_eq!(text(&s, &format!("A{}", last - 1)), "Total Sum of Sales");
+        assert_eq!(text(&s, &format!("A{last}")), "Total Sum of Units");
+        assert_eq!(val(&s, &format!("D{last}")), Value::Number(72.0));
+    }
+
     #[test]
     fn refresh_after_source_edits() {
         let mut s = sales();
@@ -2039,4 +2274,38 @@ mod tests {
         assert!(e.contains("field name is not valid"), "{e}");
         assert!(s.execute("insert.pivotTable", json!({"source": "NoSuchTable"})).is_err());
     }
+
+    #[test]
+    fn too_many_value_columns_are_refused() {
+        let mut s = Session::new();
+        s.new_workbook();
+        let mut records: Vec<Json> = vec![json!(["Cat", "Sub", "V"])];
+        for r in 0..64 {
+            for c in 0..64 {
+                records.push(json!([format!("c{r}"), format!("s{c}"), 1.0]));
+            }
+        }
+        s.execute("range.setValues", json!({"range": "A1", "values": records})).unwrap();
+        let req = |n: usize| {
+            let values: Vec<Json> = (0..n).map(|_| json!({"field": "V"})).collect();
+            json!({"source": "A1:C4097", "rows": ["Cat"], "columns": ["Sub"], "values": values})
+        };
+        let e = s.execute("insert.pivotTable", req(256)).unwrap_err().to_string();
+        assert!(e.contains("will not fit"), "{e}");
+        assert!(s.execute("insert.pivotTable", req(128)).is_ok());
+    }
+
+    #[test]
+    fn collapsed_column_items_count_as_one_column_group() {
+        let mut s = Session::new();
+        s.new_workbook();
+        let mut records: Vec<Json> = vec![json!(["Grp", "Sub", "V"])];
+        records.extend((0..64).map(|c| json!(["g", format!("s{c}"), 1.0])));
+        s.execute("range.setValues", json!({"range": "A1", "values": records})).unwrap();
+        let values: Vec<Json> = (0..256).map(|_| json!({"field": "V"})).collect();
+        s.execute("insert.pivotTable", json!({"source": "A1:C65", "columns": ["Grp"], "values": values})).unwrap();
+        s.execute("pivot.collapse", json!({"field": "Grp"})).unwrap();
+        // 64 Sub items under the collapsed "g" show as one column group: (1 + grand total) x 256 columns fit.
+        s.execute("pivot.addField", json!({"field": "Sub", "area": "columns"})).unwrap();
+    }
 }
diff --git a/crates/engine/src/cmd/print.rs b/crates/engine/src/cmd/print.rs
index 986351e..cc1dc86 100644
--- a/crates/engine/src/cmd/print.rs
+++ b/crates/engine/src/cmd/print.rs
@@ -391,7 +391,7 @@ pub struct HfContext {
 
 /// Today's date and the current time as headers and footers show them (`&D`, `&T`).
 pub fn hf_date_time(wb: &Workbook) -> (String, String) {
-    let now = gridcraft_calc::now_serial();
+    let now = gridcraft_core::date::serial_in_system(wb.date_system, gridcraft_calc::now_serial());
     let date = crate::display::format(&Value::Number(now.floor()), "m/d/yyyy", wb).text;
     let time = crate::display::format(&Value::Number(now), "h:mm AM/PM", wb).text;
     (date, time)
@@ -1765,6 +1765,14 @@ mod tests {
         }
     }
 
+    #[test]
+    fn header_footer_date_follows_the_workbook_date_system() {
+        let mut wb = Workbook::new();
+        let date_1900 = hf_date_time(&wb).0;
+        wb.date_system = gridcraft_core::DateSystem::D1904;
+        assert_eq!(hf_date_time(&wb).0, date_1900);
+    }
+
     #[test]
     fn header_footer_section_edits_are_undoable_and_views_are_per_sheet() {
         let mut s = s();
@@ -2046,6 +2054,23 @@ mod tests {
         assert!(s.execute("file.exportPdf", json!({})).is_ok());
     }
 
+    #[test]
+    fn export_pdf_without_a_path_returns_bytes_and_never_opens_a_dialog() {
+        let mut s = s();
+        for params in [json!({}), json!({"path": ""}), json!({"path": null})] {
+            let r = s.execute("file.exportPdf", params).unwrap();
+            assert!(r.get("path").is_none(), "no file is written without a path");
+            let bytes = crate::io::base64_decode(r["base64"].as_str().unwrap()).unwrap();
+            assert!(bytes.starts_with(b"%PDF-"));
+        }
+        assert!(s.take_ui_requests().is_empty(), "a programmatic call never queues a dialog");
+        // Headless callers (CLI, MCP) get the same bytes, not an error.
+        assert!(s.execute_headless("file.exportPdf", json!({})).is_ok());
+        // With no workbook open it is a clear error, not a panic.
+        let mut none = Session::new();
+        assert!(none.execute("file.exportPdf", json!({})).is_err());
+    }
+
     #[test]
     fn bands_unit() {
         let b = bands(0, 9, |_| 10.0, |_| 35.0, &[], 100);
diff --git a/crates/engine/src/cmd/sheet.rs b/crates/engine/src/cmd/sheet.rs
index f05b77d..4820905 100644
--- a/crates/engine/src/cmd/sheet.rs
+++ b/crates/engine/src/cmd/sheet.rs
@@ -249,10 +249,14 @@ fn cancel_copy_mode(s: &mut Session) {
 
 fn insert_lines(s: &mut Session, p: &Json, axis: Axis) -> Result<Json> {
     let (at, count) = lines(s, p, axis)?;
+    let limit = if axis == Axis::Rows { MAX_ROWS } else { MAX_COLS };
+    if at.checked_add(count).is_none_or(|end| end > limit) {
+        let cmd = if axis == Axis::Rows { "home.insertRows" } else { "home.insertColumns" };
+        return Err(bad(cmd, "the inserted lines would extend past the end of the worksheet"));
+    }
     check_lines_protection(s, p, axis, at, count, true)?;
     let sheet = target_sheet(s, p)?;
     // Refuse to push data off the sheet.
-    let limit = if axis == Axis::Rows { MAX_ROWS } else { MAX_COLS };
     if let Some(u) = s.doc()?.wb.sheet(sheet).and_then(|sh| sh.used_range()) {
         let last = if axis == Axis::Rows { u.end.row } else { u.end.col };
         if last >= at && last as u64 + count as u64 >= limit as u64 {
@@ -290,6 +294,9 @@ fn insert_lines(s: &mut Session, p: &Json, axis: Axis) -> Result<Json> {
 
 fn delete_lines(s: &mut Session, p: &Json, axis: Axis) -> Result<Json> {
     let (at, count) = lines(s, p, axis)?;
+    let limit = if axis == Axis::Rows { MAX_ROWS } else { MAX_COLS };
+    // Deleting past the last line only removes up to the end of the worksheet.
+    let count = count.min(limit.saturating_sub(at)).max(1);
     check_lines_protection(s, p, axis, at, count, false)?;
     let sheet = target_sheet(s, p)?;
     let out = edit(s, |cx| {
diff --git a/crates/engine/src/cmd/solver.rs b/crates/engine/src/cmd/solver.rs
index 5759f54..4465874 100644
--- a/crates/engine/src/cmd/solver.rs
+++ b/crates/engine/src/cmd/solver.rs
@@ -14,18 +14,25 @@
 //!   projection. It finds a local optimum of a smooth model; integer constraints use a small
 //!   branch and bound on top.
 //!
+//! - **Evolutionary**: a genetic search for models that aren't smooth (IF, lookups, rounding),
+//!   with tournament selection, blend crossover and Gaussian mutation inside the variable bounds,
+//!   feasibility-first ranking and integer rounding, followed by a compass (pattern) search around
+//!   the best member. It stops when the population has converged, when the best member stops
+//!   improving, or at the evaluation budget.
+//!
 //! Work is bounded by an evaluation budget (no clock: `Instant` traps on wasm). The model is
 //! saved as hidden sheet-scoped names (`solver_opt`, `solver_adj`, `solver_lhs1`…), so it
 //! travels with the workbook through XLSX.
 
 use gridcraft_core::{CellRef, RangeRef, Value};
-use gridcraft_model::{Cell, DefinedName, Workbook};
+use gridcraft_model::{Cell, DefinedName, Sheet, Workbook};
 use serde_json::{Value as Json, json};
 
 use super::whatif::Trial;
 use super::*;
 
 const CMD: &str = "data.solver";
+const REPORT_CMD: &str = "data.solverReport";
 /// Excel's limit on decision variables.
 const MAX_VARS: usize = 200;
 /// Most scalar constraints (after expanding ranges).
@@ -36,20 +43,34 @@ const MAX_EVALS: u64 = 200_000;
 const LP_WORK: u64 = 2_000_000_000;
 const MAX_NODES_LP: usize = 10_000;
 const MAX_NODES_NLP: usize = 200;
+/// Evolutionary population sizes.
+const MIN_POPULATION: usize = 10;
+const MAX_POPULATION: usize = 1000;
 /// Constraint precision (Excel's default 0.000001).
 const PRECISION: f64 = 1e-6;
 const EPS: f64 = 1e-9;
 
 pub fn specs() -> Vec<CommandSpec> {
-    vec![cmd!(
-        "data.solver",
-        "Solver…",
-        ["Data", "Analysis"],
-        None,
-        "{objective: \"B10\" (formula cell), goal?: max|min|value (default max), value?: number (for goal value), variables: \"B2:B4,D1\" (≤200 constant cells, same sheet), constraints?: [\"B5 <= 10\", \"B2:B4 >= C2:C4\", \"B2 int\", \"B3 bin\", {lhs: \"B6\", op: \"=\", rhs: 3 | \"C6\"}], nonNegative?: bool (default true: variables without a lower bound get 0), method?: grg|simplex (default grg), keep?: bool (default true; false restores the original values), saveModel?: bool (default true: hidden solver_* names), maxEvaluations?: 20000, integerOptimality?: percent (default 0), saved?: bool (solve the sheet's saved model; other params override)} → {status: optimal|converged|iterationLimit|infeasible|unbounded|notLinear, message, objective, values: {cell: value}, evaluations, changed}. No `objective` → {model: the saved model} (the menu opens the dialog).",
-        has_doc,
-        run
-    )]
+    vec![
+        cmd!(
+            "data.solver",
+            "Solver…",
+            ["Data", "Analysis"],
+            None,
+            "{objective: \"B10\" (formula cell), goal?: max|min|value (default max), value?: number (for goal value), variables: \"B2:B4,D1\" (≤200 constant cells, same sheet), constraints?: [\"B5 <= 10\", \"B2:B4 >= C2:C4\", \"B2 int\", \"B3 bin\", {lhs: \"B6\", op: \"=\", rhs: 3 | \"C6\"}], nonNegative?: bool (default true: variables without a lower bound get 0), method?: grg|simplex|evolutionary (default grg), populationSize?: 100, mutationRate?: 0.075, randomSeed?: 0 (a fixed seed, so runs repeat), convergence?: 0.0001, generationsWithoutImprovement?: 50, requireBounds?: bool (default true: every variable needs both bounds; false searches within ±100 of the start) (Evolutionary options), keep?: bool (default true; false restores the original values), saveModel?: bool (default true: hidden solver_* names), maxEvaluations?: 20000, integerOptimality?: percent (default 0), saved?: bool (solve the sheet's saved model; other params override), reports?: [answer|limits] (written on new sheets when a solution is found)} → {status: optimal|converged|cannotImprove|iterationLimit|infeasible|unbounded|notLinear, message, objective, values: {cell: value}, original: {cell: value}, model: the model as params, evaluations, changed, reports?: [sheet names]}. No `objective` → {model: the saved model} (the menu opens the dialog).",
+            has_doc,
+            run
+        ),
+        cmd!(
+            "data.solverReport",
+            "Solver Reports",
+            [],
+            None,
+            "{reports: [answer|limits], values?: {cell: number} (the solution; default the variable cells' current values), original?: {cell: number} (the values before solving; default `values`), message?: text (the result line), model?: data.solver params (default the sheet's saved model, with any data.solver params given here over it)} → {sheets: [names]}. Writes Answer and Limits reports on new sheets before the model's sheet; Limits needs Simplex LP or GRG Nonlinear and no integer constraints. data.solver's result can be passed as is.",
+            has_doc,
+            report
+        ),
+    ]
 }
 
 // ---------------------------------------------------------------- model
@@ -132,6 +153,38 @@ enum Goal {
 enum Method {
     Simplex,
     Grg,
+    Evolutionary,
+}
+
+/// The Evolutionary method's options (Solver Options › Evolutionary). The search keeps no
+/// clock, so the time without improvement is counted in generations.
+#[derive(Clone, Copy, Debug, PartialEq)]
+struct EvoOptions {
+    population: usize,
+    mutation: f64,
+    seed: u64,
+    convergence: f64,
+    stall: u64,
+    require_bounds: bool,
+}
+
+impl Default for EvoOptions {
+    fn default() -> EvoOptions {
+        EvoOptions { population: 100, mutation: 0.075, seed: 0, convergence: 1e-4, stall: 50, require_bounds: true }
+    }
+}
+
+fn evo_options(p: &Json) -> EvoOptions {
+    let d = EvoOptions::default();
+    let num = |k: &str| p.get(k).and_then(Json::as_f64).or_else(|| str_param(p, k).and_then(num_text)).filter(|v| v.is_finite());
+    EvoOptions {
+        population: num("populationSize").map_or(d.population, |v| v.clamp(MIN_POPULATION as f64, MAX_POPULATION as f64) as usize),
+        mutation: num("mutationRate").map_or(d.mutation, |v| v.clamp(0.0, 1.0)),
+        seed: num("randomSeed").map_or(d.seed, |v| v.clamp(0.0, f64::from(u32::MAX)) as u64),
+        convergence: num("convergence").map_or(d.convergence, |v| v.clamp(0.0, 1.0)),
+        stall: num("generationsWithoutImprovement").map_or(d.stall, |v| v.clamp(1.0, 100_000.0) as u64),
+        require_bounds: bool_param(p, "requireBounds").unwrap_or(d.require_bounds),
+    }
 }
 
 #[derive(Clone, Debug)]
@@ -144,6 +197,7 @@ struct Model {
     cons: Vec<Constraint>,
     non_negative: bool,
     method: Method,
+    evo: EvoOptions,
 }
 
 /// Cells of `"B2:B4,D1"` on one sheet (row-major per area, in order), at most `cap`.
@@ -301,10 +355,10 @@ fn parse_model(s: &Session, p: &Json) -> Result<Model> {
     let method = match str_param(p, "method").unwrap_or("grg").to_ascii_lowercase().replace([' ', '_', '-'], "").as_str() {
         "grg" | "grgnonlinear" | "nonlinear" => Method::Grg,
         "simplex" | "simplexlp" | "lp" | "linear" => Method::Simplex,
-        "evolutionary" => return Err(EngineError::Other("The Evolutionary method isn't available; use GRG Nonlinear or Simplex LP.".into())),
-        m => return Err(bad(CMD, format!("unknown method `{m}` (grg or simplex)"))),
+        "evolutionary" | "evo" | "genetic" => Method::Evolutionary,
+        m => return Err(bad(CMD, format!("unknown method `{m}` (grg, simplex or evolutionary)"))),
     };
-    Ok(Model { sheet, objective, goal, vars, vars_text, cons, non_negative, method })
+    Ok(Model { sheet, objective, goal, vars, vars_text, cons, non_negative, method, evo: evo_options(p) })
 }
 
 // ---------------------------------------------------------------- saved model
@@ -359,7 +413,18 @@ fn save_model(wb: &mut Workbook, m: &Model) {
     }
     put("solver_num".into(), m.cons.len().to_string());
     put("solver_neg".into(), if m.non_negative { "1" } else { "2" }.into());
-    put("solver_eng".into(), if m.method == Method::Simplex { "2" } else { "1" }.into());
+    let eng = match m.method {
+        Method::Grg => "1",
+        Method::Simplex => "2",
+        Method::Evolutionary => "3",
+    };
+    put("solver_eng".into(), eng.into());
+    if m.method == Method::Evolutionary {
+        put("solver_ssz".into(), m.evo.population.to_string());
+        put("solver_mrt".into(), m.evo.mutation.to_string());
+        put("solver_rsd".into(), m.evo.seed.to_string());
+        put("solver_rbv".into(), if m.evo.require_bounds { "1" } else { "2" }.into());
+    }
     put("solver_ver".into(), "3".into());
 }
 
@@ -398,15 +463,72 @@ pub fn saved_model(wb: &Workbook, sheet: usize) -> Option<Json> {
             }
         });
     }
-    Some(json!({
+    let method = match get("solver_eng").as_deref().map(str::trim) {
+        Some("2") => "simplex",
+        Some("3") => "evolutionary",
+        _ => "grg",
+    };
+    let mut model = json!({
         "objective": objective,
         "goal": goal,
         "value": value,
         "variables": get("solver_adj").map(local).unwrap_or_default(),
         "constraints": constraints,
         "nonNegative": get("solver_neg").as_deref().map(str::trim) != Some("2"),
-        "method": if get("solver_eng").as_deref().map(str::trim) == Some("2") { "simplex" } else { "grg" },
-    }))
+        "method": method,
+    });
+    for (name, key) in [("solver_ssz", "populationSize"), ("solver_mrt", "mutationRate"), ("solver_rsd", "randomSeed")] {
+        if let Some(v) = get(name).and_then(|v| num_text(&v)) {
+            model[key] = json!(v);
+        }
+    }
+    if let Some(v) = get("solver_rbv") {
+        model["requireBounds"] = json!(v.trim() != "2");
+    }
+    Some(model)
+}
+
+/// The model as `data.solver` params, in the form [`saved_model`] returns (the objective
+/// qualified by its sheet).
+fn model_params(wb: &Workbook, m: &Model) -> Json {
+    let sheet = wb.sheet(m.sheet).map(|s| crate::pivot::quote_sheet(&s.name)).unwrap_or_default();
+    let (goal, value) = match m.goal {
+        Goal::Max => ("max", 0.0),
+        Goal::Min => ("min", 0.0),
+        Goal::Value(v) => ("value", v),
+    };
+    let constraints: Vec<Json> = m
+        .cons
+        .iter()
+        .map(|c| match c.rel {
+            Rel::Int | Rel::Bin => json!(format!("{} {}", c.lhs_text, c.rel.text())),
+            _ => json!(format!("{} {} {}", c.lhs_text, c.rel.text(), c.rhs_text)),
+        })
+        .collect();
+    let method = match m.method {
+        Method::Simplex => "simplex",
+        Method::Grg => "grg",
+        Method::Evolutionary => "evolutionary",
+    };
+    let mut out = json!({
+        "objective": format!("{sheet}!{}", m.objective.a1()),
+        "goal": goal,
+        "value": value,
+        "variables": m.vars_text,
+        "constraints": constraints,
+        "nonNegative": m.non_negative,
+        "method": method,
+    });
+    if m.method == Method::Evolutionary {
+        let e = &m.evo;
+        out["populationSize"] = json!(e.population);
+        out["mutationRate"] = json!(e.mutation);
+        out["randomSeed"] = json!(e.seed);
+        out["convergence"] = json!(e.convergence);
+        out["generationsWithoutImprovement"] = json!(e.stall);
+        out["requireBounds"] = json!(e.require_bounds);
+    }
+    out
 }
 
 // ---------------------------------------------------------------- evaluation
@@ -442,6 +564,8 @@ struct Evaluator {
     rows: Vec<Row>,
     evals: u64,
     budget: u64,
+    /// The Limits report: the objective is this variable itself.
+    target: Option<usize>,
 }
 
 fn as_num(v: &Value) -> f64 {
@@ -476,6 +600,10 @@ impl Evaluator {
         let vals = self.trial.run(&sets, &reads);
         let mut it = vals.iter().map(as_num);
         let f = it.next().unwrap_or(f64::NAN);
+        let f = match self.target {
+            Some(j) => x.get(j).copied().unwrap_or(f64::NAN),
+            None => f,
+        };
         let mut g = Vec::with_capacity(self.rows.len());
         for r in &self.rows {
             let l = it.next().unwrap_or(f64::NAN);
@@ -1182,6 +1310,673 @@ fn nlp(ev: &mut Evaluator, x0: &[f64], lo: &[f64], hi: &[f64], goal: Goal) -> Ou
     Outcome::Solved(x, phi, (converged || viol <= PRECISION * scale) && !out_of_budget)
 }
 
+// ---------------------------------------------------------------- evolutionary
+
+/// A small deterministic generator (SplitMix64), so a seed reproduces a run on every platform.
+struct Rng(u64);
+
+impl Rng {
+    fn new(seed: u64) -> Rng {
+        Rng(seed ^ 0x2545_F491_4F6C_DD1D)
+    }
+    fn next(&mut self) -> u64 {
+        self.0 = self.0.wrapping_add(0x9E37_79B9_7F4A_7C15);
+        let mut z = self.0;
+        z = (z ^ (z >> 30)).wrapping_mul(0xBF58_476D_1CE4_E5B9);
+        z = (z ^ (z >> 27)).wrapping_mul(0x94D0_49BB_1331_11EB);
+        z ^ (z >> 31)
+    }
+    /// Uniform in [0, 1).
+    fn uniform(&mut self) -> f64 {
+        (self.next() >> 11) as f64 / (1u64 << 53) as f64
+    }
+    fn between(&mut self, a: f64, b: f64) -> f64 {
+        a + (b - a) * self.uniform()
+    }
+    fn below(&mut self, n: usize) -> usize {
+        if n == 0 { 0 } else { usize::try_from(self.next() % n as u64).unwrap_or(0) }
+    }
+    /// Standard normal (Box–Muller).
+    fn normal(&mut self) -> f64 {
+        let u = self.uniform().max(f64::MIN_POSITIVE);
+        (-2.0 * u.ln()).sqrt() * (std::f64::consts::TAU * self.uniform()).cos()
+    }
+}
+
+/// A candidate: its point, the objective to minimise and its constraint violation.
+#[derive(Clone, Debug)]
+struct Member {
+    x: Vec<f64>,
+    phi: f64,
+    viol: f64,
+}
+
+impl Member {
+    /// Feasible beats infeasible; then the lower objective, or the smaller violation.
+    fn better(&self, o: &Member, tol: f64) -> bool {
+        match (self.viol <= tol, o.viol <= tol) {
+            (true, false) => true,
+            (false, true) => false,
+            (true, true) => self.phi < o.phi,
+            (false, false) => self.viol < o.viol,
+        }
+    }
+}
+
+/// Why the Evolutionary search stopped.
+#[derive(Clone, Copy, Debug, PartialEq)]
+enum EvoEnd {
+    /// Almost all of the population is within Convergence of the best member.
+    Converged,
+    /// The best member didn't improve for the set number of generations.
+    Stalled,
+    /// The evaluation budget ran out.
+    Budget,
+}
+
+/// The search box, integer flags and scoring shared by the genetic and pattern phases.
+struct EvoSearch<'a> {
+    ev: &'a mut Evaluator,
+    rows: Vec<Row>,
+    senses: Vec<Sense>,
+    goal: Goal,
+    lo: Vec<f64>,
+    hi: Vec<f64>,
+    integer: &'a [bool],
+    tol: f64,
+}
+
+impl EvoSearch<'_> {
+    /// Clamps into the box and rounds integer variables.
+    fn repair(&self, x: &mut [f64]) {
+        for (j, v) in x.iter_mut().enumerate() {
+            let (l, h) = (self.lo.get(j).copied().unwrap_or(0.0), self.hi.get(j).copied().unwrap_or(0.0));
+            *v = if v.is_finite() { v.clamp(l, h) } else { l };
+            if self.integer.get(j).copied().unwrap_or(false) {
+                *v = v.round().clamp(l.ceil(), h.floor());
+            }
+        }
+    }
+
+    /// Scores `x`; `None` once the budget is spent.
+    fn score(&mut self, x: Vec<f64>) -> Option<Member> {
+        let p = self.ev.eval(&x)?;
+        let (phi, cons) = shape(&p, &self.rows, self.goal);
+        let viol = violation(&cons, &self.senses);
+        let phi = if phi.is_finite() { phi } else { f64::INFINITY };
+        let viol = if viol.is_finite() && cons.iter().all(|c| c.is_finite()) { viol } else { f64::INFINITY };
+        Some(Member { x, phi, viol })
+    }
+}
+
+/// The Evolutionary method within `lo..hi` from `x0`.
+fn evolutionary(ev: &mut Evaluator, x0: &[f64], lo: &[f64], hi: &[f64], integer: &[bool], goal: Goal, o: &EvoOptions) -> (Outcome, EvoEnd) {
+    let rows = ev.rows.clone();
+    let senses: Vec<Sense> = rows.iter().map(|r| r.sense).collect();
+    let scale = rows.iter().map(|r| r.rhs_const.abs()).fold(1.0, f64::max);
+    let mut start = x0.to_vec();
+    project(&mut start, lo, hi);
+    // Without a bound, search within 100 of the start.
+    let blo: Vec<f64> = lo.iter().zip(&start).map(|(l, s)| if l.is_finite() { *l } else { s - 100.0 }).collect();
+    let bhi: Vec<f64> = hi.iter().zip(&start).map(|(h, s)| if h.is_finite() { *h } else { s + 100.0 }).collect();
+    let no_integer = blo.iter().zip(&bhi).zip(integer).any(|((l, h), int)| *int && l.ceil() > h.floor());
+    if blo.iter().zip(&bhi).any(|(l, h)| l > h) || no_integer {
+        return (Outcome::Infeasible, EvoEnd::Converged);
+    }
+    let span: Vec<f64> = blo.iter().zip(&bhi).map(|(l, h)| (h - l).max(1e-9)).collect();
+    let mut se = EvoSearch { ev, rows, senses, goal, lo: blo, hi: bhi, integer, tol: PRECISION * scale };
+    let mut rng = Rng::new(o.seed);
+    let size = o.population.clamp(MIN_POPULATION, MAX_POPULATION);
+    let tol = se.tol;
+    let mut end = EvoEnd::Budget;
+    // The first generation: the start and random points in the box.
+    let mut pop: Vec<Member> = Vec::with_capacity(size);
+    se.repair(&mut start);
+    let mut next_x = Some(start);
+    while pop.len() < size {
+        let x = next_x.take().unwrap_or_else(|| {
+            let mut x: Vec<f64> = se.lo.iter().zip(&se.hi).map(|(l, h)| rng.between(*l, *h)).collect();
+            se.repair(&mut x);
+            x
+        });
+        match se.score(x) {
+            Some(m) => pop.push(m),
+            None => break,
+        }
+    }
+    let mut best: Option<Member> = None;
+    for m in &pop {
+        if best.as_ref().is_none_or(|b| m.better(b, tol)) {
+            best = Some(m.clone());
+        }
+    }
+    let mut last_improved = 0u64;
+    let mut generation = 0u64;
+    'search: while pop.len() == size {
+        let Some(b) = best.clone() else { break };
+        // Converged: 99% of the population is feasible and within Convergence of the best.
+        let close = pop.iter().filter(|m| m.viol <= tol && (m.phi - b.phi).abs() <= o.convergence * b.phi.abs().max(1.0)).count();
+        if b.viol <= tol && generation >= 5 && close * 100 >= size * 99 {
+            end = EvoEnd::Converged;
+            break;
+        }
+        if generation.saturating_sub(last_improved) >= o.stall {
+            end = EvoEnd::Stalled;
+            break;
+        }
+        // The next generation: the best survives, the rest are children of two tournaments.
+        let mut next = Vec::with_capacity(size);
+        next.push(b.clone());
+        while next.len() < size {
+            let mut parent = || {
+                let (i, k) = (rng.below(size), rng.below(size));
+                match (pop.get(i), pop.get(k)) {
+                    (Some(p), Some(q)) => Some(if q.better(p, tol) { q.x.clone() } else { p.x.clone() }),
+                    _ => None,
+                }
+            };
+            let (Some(pa), Some(pb)) = (parent(), parent()) else { break 'search };
+            let mut x: Vec<f64> = pa
+                .iter()
+                .zip(&pb)
+                .zip(&span)
+                .map(|((a, c), w)| {
+                    let mut v = a + rng.between(-0.25, 1.25) * (c - a);
+                    if rng.uniform() < o.mutation {
+                        v += 0.1 * w * rng.normal();
+                    }
+                    v
+                })
+                .collect();
+            se.repair(&mut x);
+            match se.score(x) {
+                Some(m) => next.push(m),
+                None => break 'search,
+            }
+        }
+        generation += 1;
+        for m in &next {
+            let Some(cur) = &best else { continue };
+            if m.better(cur, tol) {
+                let improved = cur.viol > tol || cur.phi - m.phi > 1e-9 * cur.phi.abs().max(1.0);
+                best = Some(m.clone());
+                if improved {
+                    last_improved = generation;
+                }
+            }
+        }
+        pop = next;
+    }
+    // Polish: a compass search on the continuous variables around the best member.
+    if let Some(mut b) = best.clone() {
+        let mut step: Vec<f64> = span.iter().map(|w| 0.01 * w).collect();
+        let n = b.x.len();
+        'polish: for _ in 0..10_000 {
+            if step.iter().zip(&span).zip(integer).all(|((s, w), int)| *int || *s <= 1e-9 * w.max(1.0)) {
+                break;
+            }
+            let mut moved = false;
+            for j in 0..n {
+                if integer.get(j).copied().unwrap_or(false) {
+                    continue;
+                }
+                for dir in [1.0, -1.0] {
+                    let mut x = b.x.clone();
+                    if let (Some(v), Some(s)) = (x.get_mut(j), step.get(j)) {
+                        *v += dir * s;
+                    }
+                    se.repair(&mut x);
+                    if x == b.x {
+                        continue;
+                    }
+                    let Some(m) = se.score(x) else { break 'polish };
+                    if m.better(&b, tol) {
+                        b = m;
+                        moved = true;
+                        break;
+                    }
+                }
+            }
+            if !moved {
+                for s in &mut step {
+                    *s *= 0.5;
+                }
+            }
+        }
+        best = Some(b);
+    }
+    match best {
+        Some(b) if b.viol <= tol => (Outcome::Solved(b.x, b.phi, end != EvoEnd::Budget), end),
+        _ if end == EvoEnd::Budget => (Outcome::Limit, end),
+        _ => (Outcome::Infeasible, end),
+    }
+}
+
+/// What a solve ended with, and why Simplex LP or Evolutionary stopped.
+struct Solve {
+    outcome: Outcome,
+    not_linear: bool,
+    evo_end: Option<EvoEnd>,
+}
+
+/// Runs the model's method for `goal` within `lo..hi` from `x0`.
+#[allow(clippy::too_many_arguments)]
+fn optimise(ev: &mut Evaluator, m: &Model, goal: Goal, x0: &[f64], lo: &[f64], hi: &[f64], integer: &[bool], gap: f64) -> Solve {
+    let any_int = integer.iter().any(|b| *b);
+    let mut not_linear = false;
+    let mut evo_end = None;
+    let outcome = if lo.iter().zip(hi).any(|(l, h)| l > h) {
+        Outcome::Infeasible
+    } else {
+        match m.method {
+            Method::Simplex => match linearize(ev, x0) {
+                Err("nonlinear") | Err("error") => {
+                    not_linear = true;
+                    Outcome::Infeasible
+                }
+                Err(_) => Outcome::Limit,
+                Ok(((cf, f_const), lin)) => {
+                    let mut rows: Vec<(Vec<f64>, Sense, f64)> = lin.iter().zip(&ev.rows).map(|((a, k), r)| (a.clone(), r.sense, -k)).collect();
+                    let c: Vec<f64> = match goal {
+                        Goal::Max => cf.iter().map(|v| -v).collect(),
+                        Goal::Min => cf.clone(),
+                        Goal::Value(v) => {
+                            rows.push((cf.clone(), Sense::Eq, v - f_const));
+                            vec![0.0; cf.len()]
+                        }
+                    };
+                    let size = (rows.len() as u64 + 2 * x0.len() as u64 + 1) * (4 * x0.len() as u64 + 2 * rows.len() as u64 + 1);
+                    let mut work = LP_WORK.max(size);
+                    let mut relax = |l: &[f64], h: &[f64]| solve_lp(&c, &rows, l, h, &mut work);
+                    if any_int { branch_and_bound(lo, hi, integer, MAX_NODES_LP, gap, &mut relax).0 } else { relax(lo, hi) }
+                }
+            },
+            Method::Grg => {
+                if any_int {
+                    let mut relax = |l: &[f64], h: &[f64]| {
+                        let mut start = x0.to_vec();
+                        project(&mut start, l, h);
+                        nlp(ev, &start, l, h, goal)
+                    };
+                    branch_and_bound(lo, hi, integer, MAX_NODES_NLP, gap, &mut relax).0
+                } else {
+                    nlp(ev, x0, lo, hi, goal)
+                }
+            }
+            Method::Evolutionary => {
+                let (out, end) = evolutionary(ev, x0, lo, hi, integer, goal, &m.evo);
+                evo_end = Some(end);
+                out
+            }
+        }
+    };
+    Solve { outcome, not_linear, evo_end }
+}
+
+// ---------------------------------------------------------------- reports
+
+#[derive(Clone, Copy, Debug, PartialEq)]
+enum ReportKind {
+    Answer,
+    Limits,
+}
+
+impl ReportKind {
+    fn title(self) -> &'static str {
+        match self {
+            ReportKind::Answer => "Answer",
+            ReportKind::Limits => "Limits",
+        }
+    }
+}
+
+/// The `reports` list (`None` when absent).
+fn report_kinds(cmd: &'static str, p: &Json) -> Result<Option<Vec<ReportKind>>> {
+    let Some(list) = p.get("reports") else { return Ok(None) };
+    let list = list.as_array().ok_or_else(|| bad(cmd, "`reports` must be an array of answer and limits"))?;
+    let mut kinds = Vec::new();
+    for k in list {
+        let kind = match k.as_str().map(|t| t.trim().to_ascii_lowercase()).as_deref() {
+            Some("answer") => ReportKind::Answer,
+            Some("limits") => ReportKind::Limits,
+            _ => return Err(bad(cmd, format!("unknown report {k} (answer or limits)"))),
+        };
+        if !kinds.contains(&kind) {
+            kinds.push(kind);
+        }
+    }
+    Ok(Some(kinds))
+}
+
+/// A report's cells: (row, column, value, bold).
+type Lines = Vec<(u32, u32, Value, bool)>;
+
+fn abs_ref(c: CellRef) -> String {
+    format!("${}${}", gridcraft_core::col_to_letters(c.col), u64::from(c.row) + 1)
+}
+
+/// A cell's name in the reports: the nearest text to its left and the nearest text above it.
+fn cell_name(sh: &Sheet, c: CellRef) -> String {
+    let text = |c: CellRef| match sh.value(c) {
+        Value::Text(t) if !t.trim().is_empty() => Some(t.to_string()),
+        _ => None,
+    };
+    let left = (0..c.col).rev().find_map(|col| text(CellRef::new(c.row, col)));
+    let top = (0..c.row).rev().find_map(|row| text(CellRef::new(row, c.col)));
+    [left, top].into_iter().flatten().collect::<Vec<_>>().join(" ")
+}
+
+fn method_name(m: Method) -> &'static str {
+    match m {
+        Method::Simplex => "Simplex LP",
+        Method::Grg => "GRG Nonlinear",
+        Method::Evolutionary => "Evolutionary",
+    }
+}
+
+/// Header labels in bold from column 1, then the rows below them; returns the next free row.
+fn table(out: &mut Lines, row: u32, headers: &[&str], rows: Vec<Vec<Value>>) -> u32 {
+    for (k, h) in headers.iter().enumerate() {
+        out.push((row, 1 + k as u32, Value::text(*h), true));
+    }
+    let mut r = row;
+    for cells in rows {
+        r = r.saturating_add(1);
+        for (k, v) in cells.into_iter().enumerate() {
+            out.push((r, 1 + k as u32, v, false));
+        }
+    }
+    r.saturating_add(2)
+}
+
+/// Everything a report describes: the model, its starting and final values, and the result.
+struct ReportInput<'a> {
+    model: &'a Model,
+    prob: &'a Problem,
+    original: Vec<f64>,
+    solution: Vec<f64>,
+    message: String,
+    budget: u64,
+}
+
+fn title(out: &mut Lines, kind: ReportKind, sheet: &str) -> u32 {
+    out.push((0, 0, Value::text(format!("GridCraft {} Report", kind.title())), true));
+    out.push((1, 0, Value::text(format!("Worksheet: {sheet}")), false));
+    3
+}
+
+fn answer_report(d: &DocState, sh: &Sheet, inp: &ReportInput) -> Lines {
+    let m = inp.model;
+    let mut trial = Trial::new(d);
+    let read = |trial: &mut Trial, x: &[f64], cells: &[CellRef]| -> Vec<f64> {
+        let sets: Vec<(usize, CellRef, Value)> = m.vars.iter().zip(x).map(|(c, v)| (m.sheet, *c, Value::number(*v))).collect();
+        let reads: Vec<(usize, CellRef)> = cells.iter().map(|c| (m.sheet, *c)).collect();
+        trial.run(&sets, &reads).iter().map(as_num).collect()
+    };
+    let f0 = read(&mut trial, &inp.original, &[m.objective]).first().copied().unwrap_or(f64::NAN);
+    // Every cell the constraints read, at the solution.
+    let mut cells = vec![m.objective];
+    for c in &m.cons {
+        cells.extend(&c.lhs);
+        if let Rhs::Cells(r) = &c.rhs {
+            cells.extend(r);
+        }
+    }
+    let vals = read(&mut trial, &inp.solution, &cells);
+    let mut at = vals.iter().copied();
+    let f1 = at.next().unwrap_or(f64::NAN);
+    let num = |v: f64| if v.is_finite() { Value::number(v) } else { Value::Error(gridcraft_core::CellError::Value) };
+    let mut out = Lines::new();
+    let mut r = title(&mut out, ReportKind::Answer, &sh.name);
+    out.push((r, 0, Value::text(format!("Result: {}", inp.message)), false));
+    out.push((r + 1, 0, Value::text(format!("Engine: {}", method_name(m.method))), false));
+    r += 3;
+    let goal = match m.goal {
+        Goal::Max => "Max".to_string(),
+        Goal::Min => "Min".to_string(),
+        Goal::Value(v) => format!("Value Of {v}"),
+    };
+    out.push((r, 0, Value::text(format!("Objective Cell ({goal})")), true));
+    let obj = vec![vec![Value::text(abs_ref(m.objective)), Value::text(cell_name(sh, m.objective)), num(f0), num(f1)]];
+    r = table(&mut out, r + 1, &["Cell", "Name", "Original Value", "Final Value"], obj);
+    out.push((r, 0, Value::text("Variable Cells"), true));
+    let kind = |j: usize| {
+        let bin = m.cons.iter().any(|c| c.rel == Rel::Bin && m.vars.get(j).is_some_and(|v| c.lhs.contains(v)));
+        match (bin, inp.prob.integer.get(j).copied().unwrap_or(false)) {
+            (true, _) => "Binary",
+            (false, true) => "Integer",
+            _ => "Contin",
+        }
+    };
+    let vars = m
+        .vars
+        .iter()
+        .enumerate()
+        .map(|(j, c)| {
+            let (a, b) = (inp.original.get(j).copied().unwrap_or(f64::NAN), inp.solution.get(j).copied().unwrap_or(f64::NAN));
+            vec![Value::text(abs_ref(*c)), Value::text(cell_name(sh, *c)), num(a), num(b), Value::text(kind(j))]
+        })
+        .collect();
+    r = table(&mut out, r + 1, &["Cell", "Name", "Original Value", "Final Value", "Integer"], vars);
+    out.push((r, 0, Value::text("Constraints"), true));
+    let mut rows = Vec::new();
+    for c in &m.cons {
+        let lhs: Vec<f64> = c.lhs.iter().map(|_| at.next().unwrap_or(f64::NAN)).collect();
+        let rhs: Vec<f64> = match &c.rhs {
+            Rhs::Cells(cells) => cells.iter().map(|_| at.next().unwrap_or(f64::NAN)).collect(),
+            Rhs::Const(v) => vec![*v],
+            Rhs::None => vec![],
+        };
+        for (k, (cell, v)) in c.lhs.iter().zip(&lhs).enumerate() {
+            let (formula, status, slack) = match (c.rel, &c.rhs) {
+                (Rel::Int, _) => (format!("{}=Integer", abs_ref(*cell)), "Binding", 0.0),
+                (Rel::Bin, _) => (format!("{}=Binary", abs_ref(*cell)), "Binding", 0.0),
+                (rel, rhs_cells) => {
+                    let b = rhs.get(k).or_else(|| rhs.first()).copied().unwrap_or(f64::NAN);
+                    let rhs_text = match rhs_cells {
+                        Rhs::Cells(cells) => cells.get(k).or_else(|| cells.first()).map(|c| abs_ref(*c)).unwrap_or_default(),
+                        _ => gridcraft_core::number_to_text(b),
+                    };
+                    let slack = (v - b).abs();
+                    let binding = rel == Rel::Eq || slack <= PRECISION * (1.0 + b.abs());
+                    let slack = if binding { 0.0 } else { slack };
+                    (format!("{}{}{rhs_text}", abs_ref(*cell), rel.text()), if binding { "Binding" } else { "Not Binding" }, slack)
+                }
+            };
+            rows.push(vec![
+                Value::text(abs_ref(*cell)),
+                Value::text(cell_name(sh, *cell)),
+                num(*v),
+                Value::text(formula),
+                Value::text(status),
+                num(slack),
+            ]);
+        }
+    }
+    table(&mut out, r + 1, &["Cell", "Name", "Cell Value", "Formula", "Status", "Slack"], rows);
+    out
+}
+
+fn limits_report(d: &DocState, sh: &Sheet, inp: &ReportInput) -> Result<Lines> {
+    let m = inp.model;
+    if inp.prob.integer.iter().any(|b| *b) {
+        return Err(EngineError::Other("The Limits report doesn't apply to models with integer or binary constraints.".into()));
+    }
+    if m.method == Method::Evolutionary {
+        return Err(EngineError::Other("The Limits report is available for Simplex LP and GRG Nonlinear.".into()));
+    }
+    let n = m.vars.len();
+    let x = &inp.solution;
+    // Each variable is minimised and maximised with the others held at the solution.
+    let per = (inp.budget / (2 * n as u64).max(1)).max(n as u64 + 3);
+    let mut ev = Evaluator {
+        trial: Trial::new(d),
+        sheet: m.sheet,
+        vars: m.vars.clone(),
+        objective: m.objective,
+        rows: inp.prob.rows.clone(),
+        evals: 0,
+        budget: 0,
+        target: None,
+    };
+    let objective_at = |ev: &mut Evaluator, x: &[f64]| {
+        ev.target = None;
+        ev.budget = ev.evals.saturating_add(1);
+        ev.eval(x).map(|p| p.f).unwrap_or(f64::NAN)
+    };
+    let num = |v: f64| if v.is_finite() { Value::number(v) } else { Value::Error(gridcraft_core::CellError::Value) };
+    let f = objective_at(&mut ev, x);
+    let mut rows = Vec::new();
+    for (j, c) in m.vars.iter().enumerate() {
+        let (mut lo, mut hi) = (x.clone(), x.clone());
+        if let (Some(l), Some(h), Some(pl), Some(ph)) = (lo.get_mut(j), hi.get_mut(j), inp.prob.lo.get(j), inp.prob.hi.get(j)) {
+            *l = *pl;
+            *h = *ph;
+        }
+        let mut ends = Vec::new();
+        for goal in [Goal::Min, Goal::Max] {
+            ev.target = Some(j);
+            ev.evals = 0;
+            ev.budget = per;
+            let solve = optimise(&mut ev, m, goal, x, &lo, &hi, &inp.prob.integer, 0.0);
+            ends.push(match solve.outcome {
+                Outcome::Solved(p, _, _) => {
+                    let v = p.get(j).copied().unwrap_or(f64::NAN);
+                    (num(v), num(objective_at(&mut ev, &p)))
+                }
+                Outcome::Unbounded => (Value::text("Unbounded"), Value::Empty),
+                _ => (Value::Error(gridcraft_core::CellError::NA), Value::Empty),
+            });
+        }
+        let mut row = vec![Value::text(abs_ref(*c)), Value::text(cell_name(sh, *c)), num(x.get(j).copied().unwrap_or(f64::NAN))];
+        for (v, o) in ends {
+            row.push(v);
+            row.push(o);
+        }
+        rows.push(row);
+    }
+    let mut out = Lines::new();
+    let r = title(&mut out, ReportKind::Limits, &sh.name);
+    let obj = vec![vec![Value::text(abs_ref(m.objective)), Value::text(cell_name(sh, m.objective)), num(f)]];
+    let r = table(&mut out, r, &["Objective Cell", "Name", "Value"], obj);
+    table(&mut out, r, &["Variable Cell", "Name", "Value", "Lower Limit", "Objective Result", "Upper Limit", "Objective Result"], rows);
+    Ok(out)
+}
+
+/// Writes the reports on new sheets ("Answer Report 1"…) before the model's sheet, in one step;
+/// the model's sheet stays active. Returns the new sheets' names.
+fn write_reports(s: &mut Session, kinds: &[ReportKind], inp: &ReportInput) -> Result<Vec<String>> {
+    if kinds.is_empty() {
+        return Ok(Vec::new());
+    }
+    let d = s.doc()?;
+    if d.wb.protected_structure {
+        return Err(EngineError::Other("The workbook is protected and cannot be changed.".into()));
+    }
+    let sh = d.wb.sheet(inp.model.sheet).ok_or(EngineError::NoDocument)?;
+    let mut built = Vec::new();
+    for k in kinds {
+        let lines = match k {
+            ReportKind::Answer => answer_report(d, sh, inp),
+            ReportKind::Limits => limits_report(d, sh, inp)?,
+        };
+        let name = (1..=10_000u32)
+            .map(|i| format!("{} Report {i}", k.title()))
+            .find(|n| d.wb.sheet_index(n).is_none() && !built.iter().any(|(b, _): &(String, Lines)| b == n))
+            .ok_or_else(|| EngineError::Other("Too many report sheets.".into()))?;
+        built.push((name, lines));
+    }
+    let names: Vec<String> = built.iter().map(|(n, _)| n.clone()).collect();
+    let at = inp.model.sheet;
+    let count = built.len();
+    edit(s, |cx| {
+        let bold = cx.wb.styles.derive(gridcraft_model::StyleId::DEFAULT, |st| st.font.bold = true);
+        for (i, (name, lines)) in built.into_iter().enumerate() {
+            let mut sheet = Sheet::new(name);
+            for (r, c, v, b) in lines {
+                let style = if b { bold } else { gridcraft_model::StyleId::DEFAULT };
+                sheet.set_cell(CellRef::new(r, c), Cell { value: v, formula: None, style });
+            }
+            for (c, w) in [(0u32, 14.0f32), (1, 110.0), (2, 140.0), (3, 120.0), (4, 120.0), (5, 120.0), (6, 120.0), (7, 120.0)] {
+                sheet.cols.insert(c, gridcraft_model::LineInfo { size: Some(w), ..Default::default() });
+            }
+            cx.wb.sheets.insert(at + i, std::sync::Arc::new(sheet));
+        }
+        for nm in cx.wb.names.iter_mut() {
+            if let Some(sc) = nm.scope.as_mut()
+                && *sc >= at
+            {
+                *sc += count;
+            }
+        }
+        if cx.wb.active_sheet >= at {
+            cx.wb.active_sheet += count;
+        }
+        cx.structural = true;
+        Ok(())
+    })?;
+    if let Ok(d) = s.doc_mut() {
+        for i in 0..count {
+            d.sheet_selections.insert((at + i).min(d.sheet_selections.len()), crate::Selection::default());
+        }
+    }
+    Ok(names)
+}
+
+/// `data.solverReport`: reports for a solution of the sheet's saved model.
+fn report(s: &mut Session, p: &Json) -> Result<Json> {
+    let kinds = report_kinds(REPORT_CMD, p)?.ok_or_else(|| bad(REPORT_CMD, "missing `reports` (answer, limits)"))?;
+    if kinds.is_empty() {
+        return Err(bad(REPORT_CMD, "`reports` is empty (answer, limits)"));
+    }
+    let d = s.doc()?;
+    // The given model as is, else the saved model with any params given here over it.
+    let params = match p.get("model") {
+        Some(m @ Json::Object(_)) => m.clone(),
+        Some(Json::Null) | None => {
+            let mut params = saved_model(&d.wb, d.wb.active_sheet).unwrap_or_else(|| json!({}));
+            if let (Some(base), Some(over)) = (params.as_object_mut(), p.as_object()) {
+                for (k, v) in over {
+                    base.insert(k.clone(), v.clone());
+                }
+            }
+            params
+        }
+        Some(_) => return Err(bad(REPORT_CMD, "`model` must be data.solver params")),
+    };
+    let model = parse_model(s, &params)?;
+    let prob = build_problem(&model);
+    let d = s.doc()?;
+    let sh = d.wb.sheet(model.sheet).ok_or(EngineError::NoDocument)?;
+    let current: Vec<f64> = model.vars.iter().map(|c| as_num(&sh.value(*c))).collect();
+    // `{cell: number}` maps; cells they leave out keep their current values.
+    let point = |key: &str| -> Result<Vec<f64>> {
+        let mut x = current.clone();
+        let Some(map) = p.get(key) else { return Ok(x) };
+        let map = map.as_object().ok_or_else(|| bad(REPORT_CMD, format!("`{key}` must map cells to numbers")))?;
+        for (cell, v) in map {
+            let c = CellRef::parse(&cell.replace('$', "")).ok_or_else(|| bad(REPORT_CMD, format!("not a cell: `{cell}`")))?;
+            let j = model.vars.iter().position(|v| *v == c).ok_or_else(|| bad(REPORT_CMD, format!("`{cell}` is not a variable cell")))?;
+            let v = v.as_f64().filter(|v| v.is_finite()).ok_or_else(|| bad(REPORT_CMD, format!("`{key}.{cell}` must be a number")))?;
+            if let Some(e) = x.get_mut(j) {
+                *e = v;
+            }
+        }
+        Ok(x)
+    };
+    let solution = point("values")?;
+    let original = if p.get("original").is_some() { point("original")? } else { solution.clone() };
+    let budget = params
+        .get("maxEvaluations")
+        .and_then(Json::as_f64)
+        .filter(|v| v.is_finite() && *v >= 1.0)
+        .map_or(DEFAULT_EVALS, |v| (v as u64).min(MAX_EVALS));
+    let message = str_param(p, "message").unwrap_or("").chars().take(500).collect();
+    let inp = ReportInput { model: &model, prob: &prob, original, solution, message, budget };
+    let sheets = write_reports(s, &kinds, &inp)?;
+    Ok(json!({"sheets": sheets}))
+}
+
 // ---------------------------------------------------------------- command
 
 fn run(s: &mut Session, p: &Json) -> Result<Json> {
@@ -1213,6 +2008,7 @@ fn run(s: &mut Session, p: &Json) -> Result<Json> {
     let gap = params.get("integerOptimality").and_then(Json::as_f64).filter(|v| v.is_finite()).map_or(0.0, |v| v.clamp(0.0, 100.0) / 100.0);
     let keep = bool_param(&params, "keep").unwrap_or(true);
     let save = bool_param(&params, "saveModel").unwrap_or(true);
+    let reports = report_kinds(CMD, &params)?;
     let prob = build_problem(&model);
     let d = s.doc()?;
     let sh = d.wb.sheet(model.sheet).ok_or(EngineError::NoDocument)?;
@@ -1225,56 +2021,23 @@ fn run(s: &mut Session, p: &Json) -> Result<Json> {
         rows: prob.rows.clone(),
         evals: 0,
         budget,
+        target: None,
     };
-    let any_int = prob.integer.iter().any(|b| *b);
-    let mut not_linear = false;
-    let outcome = if prob.lo.iter().zip(&prob.hi).any(|(l, h)| l > h) {
-        Outcome::Infeasible
-    } else {
-        match model.method {
-            Method::Simplex => match linearize(&mut ev, &x0) {
-                Err("nonlinear") | Err("error") => {
-                    not_linear = true;
-                    Outcome::Infeasible
-                }
-                Err(_) => Outcome::Limit,
-                Ok(((cf, f_const), lin)) => {
-                    let mut rows: Vec<(Vec<f64>, Sense, f64)> = lin.iter().zip(&prob.rows).map(|((a, k), r)| (a.clone(), r.sense, -k)).collect();
-                    let c: Vec<f64> = match model.goal {
-                        Goal::Max => cf.iter().map(|v| -v).collect(),
-                        Goal::Min => cf.clone(),
-                        Goal::Value(v) => {
-                            rows.push((cf.clone(), Sense::Eq, v - f_const));
-                            vec![0.0; cf.len()]
-                        }
-                    };
-                    let size = (rows.len() as u64 + 2 * model.vars.len() as u64 + 1) * (4 * model.vars.len() as u64 + 2 * rows.len() as u64 + 1);
-                    let mut work = LP_WORK.max(size);
-                    let mut relax = |l: &[f64], h: &[f64]| solve_lp(&c, &rows, l, h, &mut work);
-                    if any_int {
-                        branch_and_bound(&prob.lo, &prob.hi, &prob.integer, MAX_NODES_LP, gap, &mut relax).0
-                    } else {
-                        relax(&prob.lo, &prob.hi)
-                    }
-                }
-            },
-            Method::Grg => {
-                let goal = model.goal;
-                if any_int {
-                    let mut relax = |l: &[f64], h: &[f64]| {
-                        let mut start = x0.clone();
-                        project(&mut start, l, h);
-                        nlp(&mut ev, &start, l, h, goal)
-                    };
-                    branch_and_bound(&prob.lo, &prob.hi, &prob.integer, MAX_NODES_NLP, gap, &mut relax).0
-                } else {
-                    nlp(&mut ev, &x0, &prob.lo, &prob.hi, goal)
-                }
-            }
-        }
-    };
+    if model.method == Method::Evolutionary && model.evo.require_bounds && prob.lo.iter().chain(&prob.hi).any(|b| !b.is_finite()) {
+        return Err(EngineError::Other(
+            "The Evolutionary method needs a lower and an upper bound on every variable cell (constraints such as \"A1:A3 <= 10\"), or requireBounds: false."
+                .into(),
+        ));
+    }
+    let Solve { outcome, not_linear, evo_end } = optimise(&mut ev, &model, model.goal, &x0, &prob.lo, &prob.hi, &prob.integer, gap);
     let (status, message, solution) = match outcome {
         _ if not_linear => ("notLinear", "The model isn't linear in the variable cells, so Simplex LP can't solve it. Try GRG Nonlinear.", None),
+        Outcome::Solved(x, _, true) if model.method == Method::Evolutionary => match evo_end {
+            Some(EvoEnd::Stalled) => {
+                ("cannotImprove", "Solver stopped when the best solution stopped improving. All constraints are satisfied.", Some(x))
+            }
+            _ => ("converged", "The population converged. The best solution found satisfies all constraints.", Some(x)),
+        },
         Outcome::Solved(x, _, true) => (
             if model.method == Method::Simplex { "optimal" } else { "converged" },
             if model.method == Method::Simplex {
@@ -1303,6 +2066,7 @@ fn run(s: &mut Session, p: &Json) -> Result<Json> {
             values.insert(c.a1(), json!(v));
         }
     }
+    let original: serde_json::Map<String, Json> = model.vars.iter().zip(&x0).map(|(c, v)| (c.a1(), json!(v))).collect();
     let changed = keep && solution.is_some();
     if changed || save {
         let sheet = model.sheet;
@@ -1325,19 +2089,27 @@ fn run(s: &mut Session, p: &Json) -> Result<Json> {
             Ok(())
         })?;
     }
-    Ok(json!({
+    let mut out = json!({
         "status": status,
         "message": message,
         "objective": objective,
         "values": values,
+        "original": original,
+        "model": model_params(&s.doc()?.wb, &model),
         "evaluations": evaluations,
         "changed": changed,
-    }))
+    });
+    // Reports describe a solution; they are part of the solve's undo step.
+    if let (Some(kinds), Some(x)) = (reports, solution) {
+        let inp = ReportInput { model: &model, prob: &prob, original: x0, solution: x, message: message.to_string(), budget };
+        out["reports"] = json!(write_reports(s, &kinds, &inp)?);
+    }
+    Ok(out)
 }
 
 #[cfg(test)]
 mod tests {
-    use gridcraft_core::CellRef;
+    use gridcraft_core::{CellRef, Value};
     use serde_json::json;
 
     use crate::Session;
@@ -1351,6 +2123,11 @@ mod tests {
         let d = s.doc().unwrap();
         d.wb.active().unwrap().value(CellRef::parse(a).unwrap()).as_f64().unwrap_or(f64::NAN)
     }
+    /// The first saved-model name scoped to the active sheet.
+    fn saved(s: &Session) -> String {
+        let d = s.doc().unwrap();
+        d.wb.names.iter().find(|n| n.scope == Some(d.wb.active_sheet)).map(|n| n.name.clone()).unwrap_or_default()
+    }
     fn set(s: &mut Session, cells: &[(&str, &str)]) {
         for (c, v) in cells {
             s.execute("cell.set", json!({"cell": c, "input": v})).unwrap();
@@ -1432,6 +2209,204 @@ mod tests {
         assert!((n(&s, "E1") - 2.0).abs() < 1e-4);
     }
 
+    #[test]
+    fn evolutionary_finds_the_global_minimum_of_non_smooth_and_multimodal_models() {
+        let mut s = s();
+        // |x − 3| + |y + 2| has a kink at its minimum (3, −2).
+        set(&mut s, &[("A1", "0"), ("A2", "0"), ("B1", "=ABS(A1-3)+ABS(A2+2)")]);
+        let p =
+            json!({"objective": "B1", "goal": "min", "variables": "A1:A2", "constraints": ["A1:A2 >= -10", "A1:A2 <= 10"], "method": "evolutionary"});
+        let r = s.execute("data.solver", p.clone()).unwrap();
+        assert!(r["status"] == "converged" || r["status"] == "cannotImprove", "{r}");
+        assert!((n(&s, "A1") - 3.0).abs() < 1e-6 && (n(&s, "A2") + 2.0).abs() < 1e-6, "{r}");
+        // The same seed repeats the run exactly.
+        set(&mut s, &[("A1", "0"), ("A2", "0")]);
+        let again = s.execute("data.solver", p).unwrap();
+        assert_eq!(again["values"], r["values"]);
+        assert_eq!(again["evaluations"], r["evaluations"]);
+        // Rastrigin's function 20 + Σ (x² − 10 cos 2πx) on [−5.12, 5.12]² has its global minimum 0
+        // at the origin among many local minima; GRG from (3.3, −2.7) stops at a local one.
+        set(&mut s, &[("C1", "3.3"), ("C2", "-2.7"), ("D1", "=20+C1^2-10*COS(2*PI()*C1)+C2^2-10*COS(2*PI()*C2)")]);
+        let base = json!({"objective": "D1", "goal": "min", "variables": "C1:C2", "constraints": ["C1:C2 >= -5.12", "C1:C2 <= 5.12"]});
+        s.execute("data.solver", base.clone()).unwrap();
+        assert!(n(&s, "D1") > 0.5, "GRG is local: {}", n(&s, "D1"));
+        set(&mut s, &[("C1", "3.3"), ("C2", "-2.7")]);
+        let mut p = base.clone();
+        p["method"] = json!("evolutionary");
+        let r = s.execute("data.solver", p).unwrap();
+        assert!(n(&s, "D1") < 1e-8 && n(&s, "C1").abs() < 1e-5 && n(&s, "C2").abs() < 1e-5, "{r}");
+        // A stepped model: ROUND makes it flat almost everywhere; the minimum is at 7.2.
+        set(&mut s, &[("E1", "0"), ("F1", "=ABS(ROUND(E1,0)-7)+ABS(E1-7.2)/100")]);
+        s.execute("data.solver", json!({"objective": "F1", "goal": "min", "variables": "E1", "constraints": ["E1 <= 20"], "method": "evolutionary"}))
+            .unwrap();
+        assert!((n(&s, "E1") - 7.2).abs() < 1e-6, "{}", n(&s, "E1"));
+    }
+
+    #[test]
+    fn evolutionary_handles_integers_bounds_and_the_saved_model() {
+        let mut s = s();
+        // The 0/1 knapsack of the branch-and-bound test: items 2 and 3, value 20.
+        set(&mut s, &[("D1", "=10*C1+13*C2+7*C3"), ("D2", "=5*C1+6*C2+4*C3")]);
+        let p = json!({"objective": "D1", "variables": "C1:C3", "constraints": ["D2 <= 10", "C1:C3 bin"], "method": "evolutionary", "populationSize": 30, "randomSeed": 7});
+        let r = s.execute("data.solver", p).unwrap();
+        assert!(r["status"] == "converged" || r["status"] == "cannotImprove", "{r}");
+        assert_eq!((n(&s, "C1"), n(&s, "C2"), n(&s, "C3"), n(&s, "D1")), (0.0, 1.0, 1.0, 20.0));
+        // The method and its options are saved, survive XLSX and solve again.
+        let b64 = s.execute("file.saveBytes", json!({"format": "xlsx"})).unwrap()["base64"].as_str().unwrap().to_string();
+        s.execute("file.open", json!({"name": "e.xlsx", "base64": b64})).unwrap();
+        let m = s.execute("data.solver", json!({})).unwrap();
+        assert_eq!(m["model"]["method"], "evolutionary");
+        assert_eq!((m["model"]["populationSize"].as_f64(), m["model"]["randomSeed"].as_f64()), (Some(30.0), Some(7.0)));
+        set(&mut s, &[("C1", "0"), ("C2", "0"), ("C3", "0")]);
+        s.execute("data.solver", json!({"saved": true})).unwrap();
+        assert_eq!(n(&s, "D1"), 20.0);
+        // Integer constraints: max x + y with x + 2y ≤ 7 on integers in [0, 10] → (7, 0).
+        set(&mut s, &[("A1", "0"), ("A2", "0"), ("B1", "=A1+A2"), ("B2", "=A1+2*A2")]);
+        let r = s
+            .execute(
+                "data.solver",
+                json!({"objective": "B1", "variables": "A1:A2", "constraints": ["B2 <= 7", "A1:A2 <= 10", "A1:A2 int"], "method": "evolutionary"}),
+            )
+            .unwrap();
+        assert_eq!((n(&s, "A1"), n(&s, "A2")), (7.0, 0.0), "{r}");
+        // Every variable needs bounds unless requireBounds is off; then it searches around the start.
+        set(&mut s, &[("E1", "1"), ("F1", "=ABS(E1-4)")]);
+        let p = json!({"objective": "F1", "goal": "min", "variables": "E1", "method": "evolutionary"});
+        assert!(s.execute("data.solver", p.clone()).is_err());
+        let mut p = p;
+        p["requireBounds"] = json!(false);
+        s.execute("data.solver", p).unwrap();
+        assert!((n(&s, "E1") - 4.0).abs() < 1e-6);
+        // Infeasible constraints and a tiny budget are reported without changing the cells.
+        set(&mut s, &[("E1", "1")]);
+        let r = s
+            .execute("data.solver", json!({"objective": "F1", "variables": "E1", "constraints": ["E1 <= 3", "F1 >= 10"], "method": "evolutionary"}))
+            .unwrap();
+        assert_eq!(r["status"], "infeasible", "{r}");
+        let r = s
+            .execute(
+                "data.solver",
+                json!({"objective": "F1", "variables": "E1", "constraints": ["E1 <= 3"], "method": "evolutionary", "maxEvaluations": 3}),
+            )
+            .unwrap();
+        assert_eq!(r["status"], "iterationLimit", "{r}");
+        assert_eq!(n(&s, "E1"), 1.0);
+    }
+
+    /// Text or number at `a1` on sheet `name`.
+    fn at(s: &Session, name: &str, a1: &str) -> Value {
+        let d = s.doc().unwrap();
+        d.wb.sheet(d.wb.sheet_index(name).unwrap()).unwrap().value(CellRef::parse(a1).unwrap())
+    }
+
+    /// The row of the first cell holding `text` on sheet `name`.
+    fn row_of(s: &Session, name: &str, text: &str) -> u32 {
+        let d = s.doc().unwrap();
+        let sh = d.wb.sheet(d.wb.sheet_index(name).unwrap()).unwrap();
+        (0..60).find(|r| (0..8).any(|c| sh.value(CellRef::new(*r, c)) == Value::text(text))).unwrap()
+    }
+
+    #[test]
+    fn answer_and_limits_reports_describe_the_wyndor_glass_solution() {
+        // Wyndor Glass with labels: doors and windows across, the three plants' hours down.
+        let mut s = s();
+        s.execute(
+            "range.setValues",
+            json!({"range": "A1", "values": [[null, "Doors", "Windows", "Used", "Available"], ["Batches", 0, 0, null, null], ["Plant 1", 1, 0, null, 4], ["Plant 2", 0, 2, null, 12], ["Plant 3", 3, 2, null, 18], ["Profit", 3, 5, null, null]]}),
+        )
+        .unwrap();
+        for r in 3..=6 {
+            set(&mut s, &[(&format!("D{r}"), &format!("=SUMPRODUCT(B{r}:C{r},$B$2:$C$2)"))]);
+        }
+        let solved = s
+            .execute(
+                "data.solver",
+                json!({"objective": "D6", "variables": "B2:C2", "constraints": ["D3:D5 <= E3:E5"], "method": "simplex", "reports": ["answer", "limits"]}),
+            )
+            .unwrap();
+        assert_eq!(solved["status"], "optimal", "{solved}");
+        assert_eq!(solved["reports"], json!(["Answer Report 1", "Limits Report 1"]));
+        assert_eq!(solved["original"], json!({"B2": 0.0, "C2": 0.0}));
+        let d = s.doc().unwrap();
+        let names: Vec<&str> = d.wb.sheets.iter().map(|x| x.name.as_str()).collect();
+        assert_eq!(names, ["Answer Report 1", "Limits Report 1", "Sheet1"]);
+        assert_eq!(d.wb.active().unwrap().name, "Sheet1", "the model's sheet stays active");
+        assert_eq!(saved(&s), "solver_opt", "the saved model follows its sheet");
+        let a = "Answer Report 1";
+        assert_eq!(at(&s, a, "A1"), Value::text("GridCraft Answer Report"));
+        // Objective: $D$6 "Profit Used", from 0 to 36.
+        let r = row_of(&s, a, "$D$6");
+        assert_eq!(at(&s, a, &format!("C{}", r + 1)), Value::text("Profit Used"));
+        assert_eq!((at(&s, a, &format!("D{}", r + 1)), at(&s, a, &format!("E{}", r + 1))), (Value::number(0.0), Value::number(36.0)));
+        // Variables: doors 0 → 2, windows 0 → 6, continuous.
+        let r = row_of(&s, a, "$B$2") + 1;
+        assert_eq!(at(&s, a, &format!("C{r}")), Value::text("Batches Doors"));
+        assert_eq!(at(&s, a, &format!("E{r}")), Value::number(2.0));
+        assert_eq!(at(&s, a, &format!("F{r}")), Value::text("Contin"));
+        assert_eq!(at(&s, a, &format!("E{}", r + 1)), Value::number(6.0));
+        // Constraints: plant 1 has 2 hours to spare; plants 2 and 3 are binding.
+        let r = row_of(&s, a, "$D$3") + 1;
+        assert_eq!(at(&s, a, &format!("E{r}")), Value::text("$D$3<=$E$3"));
+        assert_eq!((at(&s, a, &format!("F{r}")), at(&s, a, &format!("G{r}"))), (Value::text("Not Binding"), Value::number(2.0)));
+        for k in 1..=2 {
+            assert_eq!((at(&s, a, &format!("F{}", r + k)), at(&s, a, &format!("G{}", r + k))), (Value::text("Binding"), Value::number(0.0)));
+        }
+        // Limits with the other variable held: doors 0..2 (profit 30..36), windows 0..6 (6..36).
+        let l = "Limits Report 1";
+        let r = row_of(&s, l, "$B$2") + 1;
+        let row = |r: u32| ["D", "E", "F", "G", "H"].map(|c| at(&s, l, &format!("{c}{r}")).as_f64().unwrap());
+        assert_eq!(row(r), [2.0, 0.0, 30.0, 2.0, 36.0]);
+        assert_eq!(row(r + 1), [6.0, 0.0, 6.0, 6.0, 36.0]);
+        // data.solverReport writes reports from the saved model and a given solution.
+        let out =
+            s.execute("data.solverReport", json!({"reports": ["answer"], "values": {"B2": 2, "C2": 6}, "original": {"B2": 1, "C2": 1}})).unwrap();
+        assert_eq!(out["sheets"], json!(["Answer Report 2"]));
+        let r = row_of(&s, "Answer Report 2", "$D$6") + 1;
+        assert_eq!(at(&s, "Answer Report 2", &format!("D{r}")), Value::number(8.0));
+        // Undo removes the reports and keeps the solution; refused requests write nothing.
+        s.execute("edit.undo", json!({})).unwrap();
+        assert_eq!(s.doc().unwrap().wb.sheets.len(), 3);
+        for p in [
+            json!({}),
+            json!({"reports": []}),
+            json!({"reports": "answer"}),
+            json!({"reports": ["population"]}),
+            json!({"reports": ["answer"], "values": {"Z9": 1}}),
+            json!({"reports": ["answer"], "values": {"B2": "x"}}),
+            json!({"reports": ["limits"], "constraints": ["D3:D5 <= E3:E5", "B2:C2 int"]}),
+            json!({"reports": ["limits"], "method": "evolutionary", "constraints": ["D3:D5 <= E3:E5", "B2:C2 <= 10"]}),
+        ] {
+            assert!(s.execute("data.solverReport", p.clone()).is_err(), "{p}");
+        }
+        assert_eq!(s.doc().unwrap().wb.sheets.len(), 3);
+        // With the solve, its reports and the saved model undone (one step), the result still
+        // describes the solution.
+        s.execute("edit.undo", json!({})).unwrap();
+        assert_eq!((s.doc().unwrap().wb.sheets.len(), n(&s, "B2")), (1, 0.0));
+        let mut p = solved.clone();
+        p["reports"] = json!(["answer"]);
+        assert_eq!(s.execute("data.solverReport", p).unwrap()["sheets"], json!(["Answer Report 1"]));
+        let r = row_of(&s, "Answer Report 1", "$B$2") + 1;
+        assert_eq!(at(&s, "Answer Report 1", &format!("E{r}")), Value::number(2.0));
+    }
+
+    #[test]
+    fn limits_report_of_a_nonlinear_model() {
+        // The largest rectangle with perimeter at most 20 (5 × 5): with the height held at 5, the
+        // width ranges over 0..5, the area over 0..25.
+        let mut s = s();
+        set(&mut s, &[("A1", "1"), ("A2", "1"), ("B1", "=A1*A2"), ("B2", "=2*A1+2*A2")]);
+        let r =
+            s.execute("data.solver", json!({"objective": "B1", "variables": "A1:A2", "constraints": ["B2 <= 20"], "reports": ["limits"]})).unwrap();
+        assert_eq!(r["reports"], json!(["Limits Report 1"]), "{r}");
+        let l = "Limits Report 1";
+        let r = row_of(&s, l, "$A$1") + 1;
+        let got: Vec<f64> = ["E", "F", "G", "H"].iter().map(|c| at(&s, l, &format!("{c}{r}")).as_f64().unwrap()).collect();
+        for (g, want) in got.iter().zip([0.0, 0.0, 5.0, 25.0]) {
+            assert!((g - want).abs() < 1e-3, "{got:?}");
+        }
+    }
+
     #[test]
     fn infeasible_unbounded_and_nonlinear_models_are_reported() {
         let mut s = s();
@@ -1469,6 +2444,7 @@ mod tests {
             json!({"objective": "B1", "variables": "A1", "goal": "sideways"}),
             json!({"objective": "B1", "variables": "A1", "goal": "value"}),
             json!({"objective": "B1", "variables": "A1", "method": "evolutionary"}),
+            json!({"objective": "B1", "variables": "A1", "method": "annealing"}),
             json!({"objective": "B1", "variables": "A1", "constraints": ["A1 ?? 3"]}),
             json!({"objective": "B1", "variables": "A1", "constraints": "A1 <= 3"}),
             json!({"objective": "B1", "variables": "A1", "constraints": ["A1:A3 <= C1:C2"]}),
diff --git a/crates/engine/src/cmd/spelling.rs b/crates/engine/src/cmd/spelling.rs
index 1f14014..1dd3df7 100644
--- a/crates/engine/src/cmd/spelling.rs
+++ b/crates/engine/src/cmd/spelling.rs
@@ -64,7 +64,14 @@ fn known(s: &Session, w: &str) -> bool {
     false
 }
 
+/// Longest word we generate suggestions for. Candidate text grows with the square of the word length, so longer
+/// tokens (no real word is this long) get no suggestions instead of an unbounded allocation.
+const MAX_SUGGEST_LEN: usize = 64;
+
 fn edits1(w: &str) -> Vec<String> {
+    if w.chars().count() > MAX_SUGGEST_LEN {
+        return Vec::new();
+    }
     let chars: Vec<char> = w.chars().collect();
     let mut out = Vec::new();
     let letters = "abcdefghijklmnopqrstuvwxyz";
@@ -177,3 +184,16 @@ fn thesaurus(_: &mut Session, p: &Json) -> Result<Json> {
     related.truncate(20);
     Ok(json!(related))
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn edits1_is_capped_for_very_long_words() {
+        assert_eq!(edits1("helo").len(), 54 * 4 + 25);
+        assert_eq!(edits1(&"a".repeat(MAX_SUGGEST_LEN)).len(), 54 * MAX_SUGGEST_LEN + 25);
+        assert!(edits1(&"a".repeat(MAX_SUGGEST_LEN + 1)).is_empty());
+        assert!(edits1(&"a".repeat(1_000_000)).is_empty());
+    }
+}
diff --git a/crates/engine/src/fill.rs b/crates/engine/src/fill.rs
index 9e0c970..5848bb0 100644
--- a/crates/engine/src/fill.rs
+++ b/crates/engine/src/fill.rs
@@ -6,6 +6,7 @@ use std::sync::Arc;
 use gridcraft_core::date::{MONTHS, WEEKDAYS, datetime_from_serial, days_in_month, serial_from_ymd};
 use gridcraft_core::{CellRef, RangeRef, Value};
 use gridcraft_model::{Cell, Formula};
+use gridcraft_numfmt::{FormatKind, NumberFormat};
 
 use crate::Result;
 use crate::cmd::Ctx;
@@ -65,21 +66,25 @@ pub fn fill(cx: &mut Ctx, sheet: usize, src: RangeRef, target: RangeRef, mode: F
                 if forward { (src.end.col + 1..=target.end.col).collect() } else { (target.start.col..src.start.col).rev().collect() };
             cols.into_iter().map(|c| CellRef::new(lane, c)).collect()
         };
+        let fmt = |c: &(CellRef, Option<Cell>)| cx.wb.styles.get(c.1.as_ref().map(|c| c.style).unwrap_or_default()).num_fmt.as_str();
         let pattern = if matches!(mode, FillMode::Series | FillMode::Alternate) {
-            let detected = Pattern::detect(
-                &src_cells,
-                &custom,
-                cx.wb.date_system,
-                cx.wb.styles.get(src_cells.first().and_then(|c| c.1.as_ref()).map(|c| c.style).unwrap_or_default()).num_fmt.as_str(),
-            );
+            let detected = Pattern::detect(&src_cells, &custom, cx.wb.date_system, src_cells.first().map(fmt).unwrap_or_default());
             if mode == FillMode::Alternate { detected.alternate(&src_cells) } else { detected }
         } else {
             Pattern::Copy
         };
+        // A source with no common pattern (`Product 1`, `On backorder`): each cell continues its
+        // own series, one step per repeat of the source.
+        let per_cell: Vec<Pattern> = if mode == FillMode::Series && matches!(pattern, Pattern::Copy) && src_cells.len() > 1 {
+            src_cells.iter().map(|c| Pattern::detect(std::slice::from_ref(c), &custom, cx.wb.date_system, fmt(c))).collect()
+        } else {
+            Vec::new()
+        };
         for (k, t) in targets.iter().enumerate() {
             let step = k as i64 + 1;
             let idx = k % src_cells.len().max(1);
-            let (sc, scell) = src_cells.get(if forward { idx } else { src_cells.len() - 1 - idx }).cloned().unwrap_or((src.start, None));
+            let src_i = if forward { idx } else { src_cells.len() - 1 - idx };
+            let (sc, scell) = src_cells.get(src_i).cloned().unwrap_or((src.start, None));
             let mut cell = scell.clone().unwrap_or_default();
             match mode {
                 FillMode::Formats => {
@@ -96,7 +101,10 @@ pub fn fill(cx: &mut Ctx, sheet: usize, src: RangeRef, target: RangeRef, mode: F
                             cell.formula = Some(Arc::new(Formula::from_expr(shifted)));
                             cell.value = Value::Empty;
                         }
-                    } else if let Some(v) = pattern.value(step, forward, src_cells.len()) {
+                    } else if let Some(v) = match per_cell.get(src_i) {
+                        Some(p) => p.value(k as i64 / src_cells.len() as i64 + 1, forward, 1),
+                        None => pattern.value(step, forward, src_cells.len()),
+                    } {
                         cell.value = v;
                     }
                     cell.style = style;
@@ -173,8 +181,14 @@ impl Pattern {
             let last = nums.last().copied().unwrap_or(0.0);
             let is_date = fmt.contains('d') || fmt.contains('y') || (fmt.contains('m') && !fmt.contains('h'));
             if nums.len() == 1 {
-                // A single number copies; a single date increments by a day.
-                return if is_date { Pattern::Linear { last, first, step: 1.0 } } else { Pattern::Copy };
+                // A single number copies; a single date increments by a day, a single time by an hour.
+                return if is_date {
+                    Pattern::Linear { last, first, step: 1.0 }
+                } else if NumberFormat::parse(fmt).kind() == FormatKind::Time {
+                    Pattern::Linear { last, first, step: 1.0 / 24.0 }
+                } else {
+                    Pattern::Copy
+                };
             }
             // Dates that differ by whole months.
             if is_date && nums.len() >= 2 {
@@ -260,8 +274,12 @@ impl Pattern {
             Pattern::TextNum { prefix, suffix, last, first, step, width } => {
                 let base = if forward { *last } else { *first };
                 let n = base + step * k * sign;
-                let n = n.abs();
-                Some(Value::text(format!("{prefix}{n:0width$}{suffix}", width = *width)))
+                // `Qtr3`, `Quarter 3` wrap after 4 like `Q3`.
+                let quarter = suffix.is_empty()
+                    && (1..=4).contains(&base)
+                    && ["q", "qtr", "quarter"].contains(&prefix.trim_end().to_ascii_lowercase().as_str());
+                let n = if quarter { (n - 1).rem_euclid(4) + 1 } else { n.abs() };
+                Some(Value::text(format!("{prefix}{n:0width$}{}", ordinal_suffix(n, suffix), width = *width)))
             }
             Pattern::List { list, last, first, step, upper, lower } => {
                 let len = list.len() as i64;
@@ -309,6 +327,23 @@ fn round15(x: f64) -> f64 {
     if !p.is_finite() || p == 0.0 { x } else { (x * p).round() / p }
 }
 
+/// `1st Period` → `2nd Period`: an English ordinal ending is rewritten to suit the new number.
+fn ordinal_suffix(n: i64, suffix: &str) -> String {
+    let (Some(end), Some(rest)) = (suffix.get(..2), suffix.get(2..)) else { return suffix.to_string() };
+    if !["st", "nd", "rd", "th"].contains(&end.to_ascii_lowercase().as_str()) || rest.starts_with(char::is_alphanumeric) {
+        return suffix.to_string();
+    }
+    let new = match (n % 10, n % 100) {
+        (_, 11..=13) => "th",
+        (1, _) => "st",
+        (2, _) => "nd",
+        (3, _) => "rd",
+        _ => "th",
+    };
+    let new = if end.chars().all(|c| c.is_ascii_uppercase()) { new.to_ascii_uppercase() } else { new.to_string() };
+    format!("{new}{rest}")
+}
+
 /// `Item 007` → ("Item ", 7, "", 3); `3rd` style leading numbers → ("", 3, "rd", 1).
 fn split_num(t: &str) -> Option<(String, i64, String, usize)> {
     let chars: Vec<char> = t.chars().collect();
@@ -338,6 +373,7 @@ pub fn series(cx: &mut Ctx, sheet: usize, r: RangeRef, rows: bool, kind: &str, s
         let style = sh.style_id(first_cell);
         let mut v = start;
         for i in 1..len {
+            let prev = v;
             v = match kind {
                 "growth" => v * step,
                 "date" => {
@@ -350,7 +386,10 @@ pub fn series(cx: &mut Ctx, sheet: usize, r: RangeRef, rows: bool, kind: &str, s
                             let mut left = step.abs() as i64;
                             while left > 0 {
                                 n += step.signum();
-                                if datetime_from_serial(sys, n).is_some_and(|d| d.weekday != 0 && d.weekday != 6) {
+                                let Some(day) = datetime_from_serial(sys, n) else {
+                                    return Err(crate::EngineError::Other("The weekday series runs past the supported date range.".into()));
+                                };
+                                if day.weekday != 0 && day.weekday != 6 {
                                     left -= 1;
                                 }
                             }
@@ -361,8 +400,9 @@ pub fn series(cx: &mut Ctx, sheet: usize, r: RangeRef, rows: bool, kind: &str, s
                 }
                 _ => v + step,
             };
+            // The stop value bounds the series in the direction it runs (a growth by 0.5 falls).
             if let Some(s) = stop
-                && ((step >= 0.0 && v > s) || (step < 0.0 && v < s))
+                && ((v >= prev && v > s) || (v < prev && v < s))
             {
                 break;
             }
@@ -579,4 +619,37 @@ mod tests {
         assert_eq!(split_num("Q003x"), Some(("Q".into(), 3, "x".into(), 3)));
         assert_eq!(split_num("abc"), None);
     }
+
+    #[test]
+    fn times_quarters_ordinals_and_mixed_sources() {
+        let mut s = crate::Session::new();
+        s.new_workbook();
+        let mut fill = |values: serde_json::Value, source: &str, target: &str| {
+            s.execute("range.setValues", serde_json::json!({"range": source.get(..2).unwrap(), "values": values})).unwrap();
+            s.execute("edit.autoFill", serde_json::json!({"source": source, "target": target})).unwrap();
+            let sh = s.doc().unwrap().wb.active().unwrap();
+            let r = RangeRef::parse(target).unwrap();
+            r.iter().map(|c| crate::display::cell_text(&s.doc().unwrap().wb, sh, c)).collect::<Vec<_>>()
+        };
+        assert_eq!(fill(serde_json::json!([["9:00"]]), "A1", "A1:A3"), ["9:00", "10:00", "11:00"]);
+        assert_eq!(fill(serde_json::json!([["Qtr3"]]), "B1", "B1:B3"), ["Qtr3", "Qtr4", "Qtr1"]);
+        assert_eq!(fill(serde_json::json!([["Quarter 4"]]), "C1", "C1:C2"), ["Quarter 4", "Quarter 1"]);
+        assert_eq!(fill(serde_json::json!([["1st Period"]]), "D1", "D1:D4"), ["1st Period", "2nd Period", "3rd Period", "4th Period"]);
+        assert_eq!(
+            fill(serde_json::json!([["Product 1"], ["On backorder"]]), "E1:E2", "E1:E6"),
+            ["Product 1", "On backorder", "Product 2", "On backorder", "Product 3", "On backorder"]
+        );
+    }
+
+    #[test]
+    fn falling_growth_series_stops_at_its_stop_value() {
+        let mut s = crate::Session::new();
+        s.new_workbook();
+        s.execute("cell.set", serde_json::json!({"cell": "A1", "input": "5"})).unwrap();
+        s.execute("edit.fillSeries", serde_json::json!({"range": "A1:A6", "type": "growth", "step": 0.5, "stop": 1})).unwrap();
+        let d = s.doc().unwrap();
+        let sh = d.wb.active().unwrap();
+        let growth: Vec<String> = (1..6).map(|r| crate::display::cell_text(&d.wb, sh, CellRef::new(r, 0))).collect();
+        assert_eq!(growth, ["2.5", "1.25", "", "", ""]);
+    }
 }
diff --git a/crates/engine/src/io.rs b/crates/engine/src/io.rs
index 5453be8..e8a17b7 100644
--- a/crates/engine/src/io.rs
+++ b/crates/engine/src/io.rs
@@ -102,6 +102,8 @@ fn open_plain(name: &str, bytes: &[u8]) -> Result<(Workbook, Vec<String>)> {
     let import = match sniffed {
         gridcraft_xlsx::Format::Ods => Some(FileKind::Ods),
         gridcraft_xlsx::Format::Xlsb => Some(FileKind::Xlsb),
+        // An XLSX package is never read as ODS/XLSB just because of its name.
+        gridcraft_xlsx::Format::Xlsx => None,
         _ => kind.filter(|k| matches!(k, FileKind::Ods | FileKind::Xlsb)),
     };
     if let Some(import) = import {
@@ -109,7 +111,8 @@ fn open_plain(name: &str, bytes: &[u8]) -> Result<(Workbook, Vec<String>)> {
         let (wb, report) = read(bytes).map_err(|e| EngineError::Other(format!("We can't import '{name}': {e}")))?;
         return Ok((wb, report.warnings));
     }
-    if sniffed == gridcraft_xlsx::Format::Xlsx || kind == Some(FileKind::Xlsx) {
+    // Text named `.xlsx` is read as text.
+    if sniffed == gridcraft_xlsx::Format::Xlsx || (kind == Some(FileKind::Xlsx) && sniffed != gridcraft_xlsx::Format::Csv) {
         let (wb, report) = gridcraft_xlsx::read_xlsx(bytes).map_err(|e| EngineError::Other(format!("We can't open '{name}': {e}")))?;
         return Ok((wb, report.warnings));
     }
@@ -153,8 +156,19 @@ fn rename_first_sheet(wb: &mut Workbook, path: &str) {
 
 /// Encodes a workbook in the format chosen by `path`'s extension.
 pub fn save_bytes(wb: &Workbook, path: &str) -> Result<Vec<u8>> {
+    // An unknown or missing extension is refused rather than written as an XLSX under that name:
+    // a typo like `.cvs` would otherwise produce a file no other app recognises.
+    let Some(kind) = FileKind::from_path(path) else {
+        let name = std::path::Path::new(path).file_name().and_then(|n| n.to_str()).unwrap_or(path);
+        return Err(EngineError::Other(format!("{name}: unknown file format. Save as .xlsx, .csv, .tsv, .json or .html.")));
+    };
+    save_bytes_as(wb, path, kind)
+}
+
+/// Encodes a workbook as `kind`, whatever `path`'s extension says.
+pub fn save_bytes_as(wb: &Workbook, path: &str, kind: FileKind) -> Result<Vec<u8>> {
     let sheet = wb.active_sheet;
-    match FileKind::from_path(path).unwrap_or(FileKind::Xlsx) {
+    match kind {
         // The extension picks the package kind; only the macro-enabled kinds (.xlsm, .xltm) carry
         // the VBA project, so any other name saves without it, as Excel does.
         FileKind::Xlsx => gridcraft_xlsx::write_xlsx_as(wb, gridcraft_xlsx::XlsxKind::from_path(path)).map_err(|e| EngineError::Other(e.to_string())),
@@ -167,7 +181,7 @@ pub fn save_bytes(wb: &Workbook, path: &str) -> Result<Vec<u8>> {
         FileKind::Csv => wb.sheet(sheet).map(|sh| csv(wb, sh, wb.csv_delimiter.unwrap_or(b','))).transpose().map(Option::unwrap_or_default),
         FileKind::Tsv => wb.sheet(sheet).map(|sh| csv(wb, sh, b'\t')).transpose().map(Option::unwrap_or_default),
         FileKind::Json => serde_json::to_vec_pretty(wb).map_err(|e| EngineError::Other(e.to_string())),
-        FileKind::Html => Ok(to_html(wb, sheet).into_bytes()),
+        FileKind::Html => to_html(wb, sheet).map(String::into_bytes),
     }
 }
 
@@ -297,9 +311,12 @@ impl std::fmt::Write for ClipboardHtml {
     }
 }
 
+/// Most rows Save as Web Page writes. A sheet whose used range is taller fails instead of losing cells.
+const HTML_EXPORT_MAX_ROWS: u32 = 100_001;
+
 /// A sheet as a standalone HTML table (Save as Web Page).
-pub fn to_html(wb: &Workbook, sheet: usize) -> String {
-    let Some(sh) = wb.sheet(sheet) else { return String::new() };
+pub fn to_html(wb: &Workbook, sheet: usize) -> Result<String> {
+    let Some(sh) = wb.sheet(sheet) else { return Ok(String::new()) };
     let mut out = String::new();
     let _ = write!(
         out,
@@ -307,7 +324,13 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> String {
         esc(&sh.name)
     );
     if let Some(r) = sh.used_range() {
-        for row in r.start.row..=r.end.row.min(r.start.row + 100_000) {
+        if r.height() > HTML_EXPORT_MAX_ROWS {
+            return Err(EngineError::Other(format!(
+                "the sheet is too tall for a web page ({} rows, at most {HTML_EXPORT_MAX_ROWS}). Save as .xlsx or CSV instead.",
+                r.height()
+            )));
+        }
+        for row in r.start.row..=r.end.row {
             if sh.is_row_hidden(row) {
                 continue;
             }
@@ -330,7 +353,7 @@ pub fn to_html(wb: &Workbook, sheet: usize) -> String {
         }
     }
     out.push_str("</table></body></html>");
-    out
+    Ok(out)
 }
 
 #[cfg(not(target_arch = "wasm32"))]
@@ -351,8 +374,12 @@ pub fn read_file(path: &str) -> Result<Vec<u8>> {
 pub fn write_file(path: &str, bytes: &[u8]) -> Result<()> {
     // Write to a temporary file, then rename: a crash never leaves a half-written workbook.
     let tmp = format!("{path}.sctmp");
-    std::fs::write(&tmp, bytes).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
-    std::fs::rename(&tmp, path).map_err(|e| EngineError::Other(format!("{path}: {e}")))
+    std::fs::write(&tmp, bytes).and_then(|()| std::fs::rename(&tmp, path)).map_err(|e| {
+        // A write or rename that fails (full disk, the workbook locked by another app) leaves
+        // no temporary file beside the user's workbook.
+        let _ = std::fs::remove_file(&tmp);
+        EngineError::Other(format!("{path}: {e}"))
+    })
 }
 
 #[cfg(target_arch = "wasm32")]
@@ -430,6 +457,20 @@ pub fn image_size(data: &[u8]) -> Option<(u32, u32)> {
 mod tests {
     use super::*;
 
+    #[test]
+    fn html_export_fails_instead_of_dropping_cells_past_the_row_limit() {
+        let mut wb = Workbook::new();
+        let sh = wb.sheet_mut(0).unwrap();
+        sh.set_value(CellRef::new(0, 0), gridcraft_core::Value::text("near"));
+        sh.set_value(CellRef::new(149_999, 0), gridcraft_core::Value::text("far"));
+        assert!(save_bytes(&wb, "book.html").is_err());
+        let sh = wb.sheet_mut(0).unwrap();
+        sh.remove_cell(CellRef::new(149_999, 0));
+        sh.set_value(CellRef::new(100_000, 0), gridcraft_core::Value::text("far"));
+        let html = String::from_utf8(save_bytes(&wb, "book.html").unwrap()).unwrap();
+        assert!(html.contains(">near</td>") && html.contains(">far</td>"));
+    }
+
     #[test]
     fn macros_are_saved_only_into_xlsm() {
         let mut wb = Workbook::new();
@@ -446,6 +487,26 @@ mod tests {
         assert!(wb.vba_project.is_some(), "the open workbook keeps its macros");
     }
 
+    /// A save that can't be put in place (here a folder already has the workbook's name, as
+    /// with a file another app holds locked) fails without leaving `<name>.sctmp` behind.
+    #[cfg(not(target_arch = "wasm32"))]
+    #[test]
+    fn failed_save_leaves_no_temporary_file() {
+        let dir = std::env::temp_dir().join(format!("gridcraft-write-{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&dir);
+        std::fs::create_dir_all(&dir).unwrap();
+        let blocked = dir.join("Book1.xlsx");
+        std::fs::create_dir(&blocked).unwrap();
+        assert!(write_file(blocked.to_str().unwrap(), b"workbook").is_err());
+        assert!(!dir.join("Book1.xlsx.sctmp").exists(), "the temporary file is removed");
+        // An ordinary save still works and leaves only the workbook.
+        let ok = dir.join("Book2.xlsx");
+        write_file(ok.to_str().unwrap(), b"workbook").unwrap();
+        assert_eq!(std::fs::read(&ok).unwrap(), b"workbook");
+        assert!(!dir.join("Book2.xlsx.sctmp").exists());
+        let _ = std::fs::remove_dir_all(&dir);
+    }
+
     /// A minimal compound (CFB/OLE2) file — FAT in sector 0, directory in sector 1 — holding a
     /// root entry and the given stream names.
     fn cfb(streams: &[&str]) -> Vec<u8> {
@@ -609,4 +670,19 @@ mod tests {
             "{types}"
         );
     }
+
+    #[test]
+    fn content_wins_over_a_mismatched_extension() {
+        let mut wb = Workbook::new();
+        wb.sheet_mut(0).unwrap().set_value(CellRef::new(0, 0), gridcraft_core::Value::Number(7.0));
+        let package = save_bytes(&wb, "book.xlsx").unwrap();
+        for name in ["book.xlsx", "book.ods", "book.xlsb", "book.csv"] {
+            let (opened, _) = open_bytes(name, &package).unwrap_or_else(|e| panic!("{name}: {e}"));
+            assert_eq!(opened.sheet(0).unwrap().value(CellRef::new(0, 0)), gridcraft_core::Value::Number(7.0), "{name}");
+        }
+        for name in ["data.xlsx", "data.csv"] {
+            let (opened, _) = open_bytes(name, b"a,b\n1,2\n").unwrap_or_else(|e| panic!("{name}: {e}"));
+            assert_eq!(opened.sheet(0).unwrap().value(CellRef::new(0, 1)), gridcraft_core::Value::text("b"), "{name}");
+        }
+    }
 }
diff --git a/crates/engine/src/lib.rs b/crates/engine/src/lib.rs
index 3aceab0..5a2e3df 100644
--- a/crates/engine/src/lib.rs
+++ b/crates/engine/src/lib.rs
@@ -108,6 +108,9 @@ pub struct DocState {
     pub sheet_selections: Vec<Selection>,
     /// Allow Edit Ranges unlocked with their password in this session: (sheet name, title).
     pub unlocked_ranges: Vec<(String, String)>,
+    /// The format `path`'s content was recognised as when its extension doesn't name one (an
+    /// XLSX called `budget.dat`): Save writes it back in that format.
+    pub content_kind: Option<io::FileKind>,
 }
 
 static NEXT_UID: std::sync::atomic::AtomicU64 = std::sync::atomic::AtomicU64::new(1);
@@ -132,6 +135,7 @@ impl DocState {
             title,
             sheet_selections: vec![],
             unlocked_ranges: vec![],
+            content_kind: None,
         }
     }
     pub fn is_dirty(&self) -> bool {
diff --git a/crates/engine/src/pivot.rs b/crates/engine/src/pivot.rs
index c76bf4b..6146bd4 100644
--- a/crates/engine/src/pivot.rs
+++ b/crates/engine/src/pivot.rs
@@ -560,6 +560,8 @@ struct Line {
     values: bool,
     /// (column, value, indent, number format)
     labels: Vec<(usize, Value, u8, Option<String>)>,
+    /// The value field of the line when Σ Values sits in Rows (`None`: one per data column).
+    vi: Option<usize>,
 }
 
 #[derive(Clone, Copy, PartialEq, Eq)]
@@ -579,6 +581,10 @@ struct Ctx<'a> {
     rows: Vec<&'a PivotField>,
     row_items: Vec<FieldItems>,
     row_fmts: Vec<String>,
+    /// Depth of Σ Values among the row fields when it sits in Rows (two or more value fields).
+    vpos: Option<usize>,
+    /// Value field captions.
+    val_names: Vec<String>,
 }
 
 impl Ctx<'_> {
@@ -588,26 +594,105 @@ impl Ctx<'_> {
         (it.value.clone(), fmt, it.label.clone())
     }
 
-    fn flatten(&self, nodes: &[Node], depth: usize, prefix: &mut Vec<u32>, out: &mut Vec<Line>) {
+    /// (column, indent) of a row level (Σ Values counts as a level) in Compact/Outline form.
+    fn level_cell(&self, level: usize) -> (usize, u8) {
+        if self.pt.layout == PivotLayout::Outline { (level, 0) } else { (0, level.min(250) as u8) }
+    }
+
+    /// Σ Values comes right here, at row field depth `depth` (`vi`: the value field already chosen above).
+    fn values_here(&self, depth: usize, vi: Option<usize>) -> bool {
+        vi.is_none() && self.vpos == Some(depth)
+    }
+
+    /// Per-value subtotal lines of an item with Σ Values below it ("East Sum of Sales").
+    fn value_subtotals(&self, col: usize, indent: u8, label: &str, prefix: &[u32], out: &mut Vec<Line>) {
+        for (vi, name) in self.val_names.iter().enumerate() {
+            out.push(Line {
+                kind: LineKind::Subtotal,
+                leaf: false,
+                path: prefix.to_vec(),
+                values: true,
+                labels: vec![(col, Value::text(format!("{label} {name}")), indent, None)],
+                vi: Some(vi),
+            });
+        }
+    }
+
+    /// The Σ Values level at row field depth `depth`: one item per value field, each followed by
+    /// the row fields below it (`nodes`) or, innermost, holding that value.
+    fn flatten_values(&self, nodes: &[Node], depth: usize, prefix: &mut Vec<u32>, out: &mut Vec<Line>) {
+        let (col, indent) = self.level_cell(depth);
+        for (vi, name) in self.val_names.iter().enumerate() {
+            let labels = vec![(col, Value::text(name.as_str()), indent, None)];
+            let leaf = nodes.is_empty();
+            out.push(Line { kind: LineKind::Item(!leaf), leaf, path: prefix.clone(), values: leaf, labels, vi: Some(vi) });
+            if !leaf {
+                self.flatten(nodes, depth, Some(vi), prefix, out);
+            }
+        }
+    }
+
+    fn flatten(&self, nodes: &[Node], depth: usize, vi: Option<usize>, prefix: &mut Vec<u32>, out: &mut Vec<Line>) {
+        if self.values_here(depth, vi) {
+            self.flatten_values(nodes, depth, prefix, out);
+            return;
+        }
         let n = self.rows.len();
-        let outline = self.pt.layout == PivotLayout::Outline;
+        // Σ Values still to come below this level: totals need one line per value field.
+        let values_below = vi.is_none() && self.vpos.is_some();
+        let (col, indent) = self.level_cell(depth + usize::from(vi.is_some() && self.vpos.is_some()));
         for node in nodes {
             prefix.push(node.item);
             let (v, fmt, label) = self.label_cell(depth, node.item);
-            let (col, indent) = if outline { (depth, 0) } else { (0, depth.min(250) as u8) };
             let collapsed = depth + 1 < n && self.rows.get(depth).is_some_and(|f| is_collapsed(f, &label));
-            if depth + 1 >= n || collapsed || node.children.is_empty() {
+            let leaf = depth + 1 >= n || collapsed || node.children.is_empty();
+            if leaf && !values_below {
                 out.push(Line {
                     kind: LineKind::Item(depth + 1 < n),
                     leaf: true,
                     path: prefix.clone(),
                     values: true,
                     labels: vec![(col, v, indent, fmt)],
+                    vi,
                 });
+            } else if leaf {
+                out.push(Line {
+                    kind: LineKind::Item(true),
+                    leaf: false,
+                    path: prefix.clone(),
+                    values: false,
+                    labels: vec![(col, v, indent, fmt)],
+                    vi,
+                });
+                // Outline gives each level its own column, so the captions go in the Values
+                // column even when the levels between are collapsed away.
+                let level = if self.pt.layout == PivotLayout::Outline { self.vpos.unwrap_or(depth + 1) } else { depth + 1 };
+                self.flatten_values(&[], level, prefix, out);
+            } else if values_below {
+                // Subtotals per value field, below the group (one line can't hold them all).
+                out.push(Line {
+                    kind: LineKind::Item(true),
+                    leaf: false,
+                    path: prefix.clone(),
+                    values: false,
+                    labels: vec![(col, v, indent, fmt)],
+                    vi,
+                });
+                self.flatten(&node.children, depth + 1, None, prefix, out);
+                if self.pt.subtotals {
+                    self.value_subtotals(col, indent, &label, prefix, out);
+                }
             } else {
                 let top = self.pt.subtotals && self.pt.subtotals_top;
-                out.push(Line { kind: LineKind::Item(true), leaf: false, path: prefix.clone(), values: top, labels: vec![(col, v, indent, fmt)] });
-                self.flatten(&node.children, depth + 1, prefix, out);
+                out.push(Line {
+                    kind: LineKind::Item(true),
+                    leaf: false,
+                    path: prefix.clone(),
+                    values: top,
+                    labels: vec![(col, v, indent, fmt)],
+                    vi,
+                });
+                self.flatten(&node.children, depth + 1, vi, prefix, out);
                 if self.pt.subtotals && !self.pt.subtotals_top {
                     out.push(Line {
                         kind: LineKind::Subtotal,
@@ -615,6 +700,7 @@ impl Ctx<'_> {
                         path: prefix.clone(),
                         values: true,
                         labels: vec![(col, Value::text(format!("{label} Total")), indent, None)],
+                        vi,
                     });
                 }
             }
@@ -622,7 +708,8 @@ impl Ctx<'_> {
         }
     }
 
-    fn flatten_tabular(
+    /// Tabular form of [`Self::flatten_values`]: the first line also carries the parents' labels.
+    fn flatten_tabular_values(
         &self,
         nodes: &[Node],
         depth: usize,
@@ -630,24 +717,57 @@ impl Ctx<'_> {
         pending: &[(usize, Value, u8, Option<String>)],
         out: &mut Vec<Line>,
     ) {
+        for (vi, name) in self.val_names.iter().enumerate() {
+            let mut labels: Vec<(usize, Value, u8, Option<String>)> = if vi == 0 { pending.to_vec() } else { vec![] };
+            labels.push((depth, Value::text(name.as_str()), 0, None));
+            if nodes.is_empty() {
+                out.push(Line { kind: LineKind::Item(false), leaf: true, path: prefix.clone(), values: true, labels, vi: Some(vi) });
+            } else {
+                self.flatten_tabular(nodes, depth, Some(vi), prefix, &labels, out);
+            }
+        }
+    }
+
+    fn flatten_tabular(
+        &self,
+        nodes: &[Node],
+        depth: usize,
+        vi: Option<usize>,
+        prefix: &mut Vec<u32>,
+        pending: &[(usize, Value, u8, Option<String>)],
+        out: &mut Vec<Line>,
+    ) {
+        if self.values_here(depth, vi) {
+            self.flatten_tabular_values(nodes, depth, prefix, pending, out);
+            return;
+        }
         let n = self.rows.len();
+        let values_below = vi.is_none() && self.vpos.is_some();
+        let col = depth + usize::from(vi.is_some() && self.vpos.is_some());
         for (i, node) in nodes.iter().enumerate() {
             prefix.push(node.item);
             let (v, fmt, label) = self.label_cell(depth, node.item);
             let mut labels: Vec<(usize, Value, u8, Option<String>)> = if i == 0 { pending.to_vec() } else { vec![] };
-            labels.push((depth, v, 0, fmt));
+            labels.push((col, v, 0, fmt));
             let collapsed = depth + 1 < n && self.rows.get(depth).is_some_and(|f| is_collapsed(f, &label));
             if depth + 1 >= n || collapsed || node.children.is_empty() {
-                out.push(Line { kind: LineKind::Item(false), leaf: true, path: prefix.clone(), values: true, labels });
+                if values_below {
+                    self.flatten_tabular_values(&[], self.vpos.unwrap_or(depth + 1), prefix, &labels, out);
+                } else {
+                    out.push(Line { kind: LineKind::Item(false), leaf: true, path: prefix.clone(), values: true, labels, vi });
+                }
             } else {
-                self.flatten_tabular(&node.children, depth + 1, prefix, &labels, out);
-                if self.pt.subtotals {
+                self.flatten_tabular(&node.children, depth + 1, vi, prefix, &labels, out);
+                if self.pt.subtotals && values_below {
+                    self.value_subtotals(col, 0, &label, prefix, out);
+                } else if self.pt.subtotals {
                     out.push(Line {
                         kind: LineKind::Subtotal,
                         leaf: false,
                         path: prefix.clone(),
                         values: true,
-                        labels: vec![(depth, Value::text(format!("{label} Total")), 0, None)],
+                        labels: vec![(col, Value::text(format!("{label} Total")), 0, None)],
+                        vi,
                     });
                 }
             }
@@ -693,6 +813,12 @@ enum ValSrc {
     Calc(usize),
 }
 
+/// True when `col_groups` distinct column leaves (plus the grand-total column) times `values` value fields
+/// (at least one data column per group) already exceed the sheet width. This is a lower bound on the final column count.
+fn data_cols_exceed_sheet(col_groups: usize, grand_total: bool, values: usize) -> bool {
+    (col_groups + usize::from(grand_total)).saturating_mul(values.max(1)) > MAX_COLS as usize
+}
+
 /// Computes a PivotTable report from the workbook.
 pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Output, String> {
     let src = read_source(wb, &pt.source, pivot_sheet)?;
@@ -745,6 +871,14 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
 
     let k = vals.len();
     let empty = rows.is_empty() && cols.is_empty() && vals.is_empty();
+    // Σ Values in Rows (it exists with two or more value fields): its depth among the row fields
+    // found in the source.
+    let vpos: Option<usize> = (pt.values_on_rows && k > 1).then(|| {
+        let p = pt.values_position.unwrap_or(pt.rows.len());
+        pt.rows.iter().take(p).filter(|f| src.col(&f.source_col).is_some()).count()
+    });
+    let on_rows = vpos.is_some();
+    let row_levels = rows.len() + usize::from(on_rows);
 
     // ---- aggregate
     let mut row_items: Vec<FieldItems> = rows.iter().map(|_| FieldItems::default()).collect();
@@ -752,6 +886,7 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
     let mut aggs: AggMap = HashMap::new();
     let mut row_set: HashSet<Vec<u32>> = HashSet::new();
     let mut col_set: HashSet<Vec<u32>> = HashSet::new();
+    let mut col_leaves: HashSet<Vec<u32>> = HashSet::new();
     let filter_fmts: Vec<String> = filters.iter().map(|f| fmt_of(f.0)).collect();
     let row_fmts: Vec<String> = rows.iter().map(|(c, _)| fmt_of(*c)).collect();
     let col_fmts: Vec<String> = cols.iter().map(|(c, _)| fmt_of(*c)).collect();
@@ -788,8 +923,22 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
                 }
             }
         }
+        // The column leaf this record lands in: its path cut after the first collapsed item (as in `flatten_cols`).
+        let shown = cols
+            .iter()
+            .zip(col_items.iter())
+            .zip(cp.iter())
+            .position(|(((_, f), fi), &it)| !f.collapsed_items.is_empty() && is_collapsed(f, &fi.label(it)))
+            .map_or(cp.len(), |d| d + 1);
+        if !col_leaves.contains(&cp[..shown]) {
+            col_leaves.insert(cp[..shown].to_vec());
+        }
         row_set.insert(rp);
         col_set.insert(cp);
+        // Refuse a report that cannot fit before the accumulators for more column groups are allocated.
+        if !cols.is_empty() && data_cols_exceed_sheet(col_leaves.len(), pt.grand_totals_rows, k) {
+            return Err("The PivotTable report will not fit on the sheet.".into());
+        }
         if aggs.len() > 5_000_000 {
             return Err("The PivotTable report is too large.".into());
         }
@@ -806,24 +955,32 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
     collect_siblings(&row_tree, &mut Vec::new(), &mut siblings);
     let level0: Vec<u32> = row_tree.iter().map(|n| n.item).collect();
 
-    let ctx = Ctx { pt, rows: row_fields.clone(), row_items, row_fmts: row_fmts.clone() };
+    let val_names: Vec<String> = vals.iter().map(|(_, v)| v.name.clone()).collect();
+    let ctx = Ctx { pt, rows: row_fields.clone(), row_items, row_fmts: row_fmts.clone(), vpos, val_names: val_names.clone() };
     let mut lines: Vec<Line> = Vec::new();
-    if rows.is_empty() {
-        lines.push(Line { kind: LineKind::Item(false), leaf: true, path: vec![], values: true, labels: vec![] });
+    if row_levels == 0 {
+        lines.push(Line { kind: LineKind::Item(false), leaf: true, path: vec![], values: true, labels: vec![], vi: None });
     } else {
         if pt.layout == PivotLayout::Tabular {
-            ctx.flatten_tabular(&row_tree, 0, &mut Vec::new(), &[], &mut lines);
+            ctx.flatten_tabular(&row_tree, 0, None, &mut Vec::new(), &[], &mut lines);
         } else {
-            ctx.flatten(&row_tree, 0, &mut Vec::new(), &mut lines);
+            ctx.flatten(&row_tree, 0, None, &mut Vec::new(), &mut lines);
         }
-        if pt.grand_totals_cols {
-            lines.push(Line {
+        // With only Σ Values in Rows its items are the totals already.
+        if pt.grand_totals_cols && !rows.is_empty() {
+            let grand = |text: String, vi: Option<usize>| Line {
                 kind: LineKind::Grand,
                 leaf: false,
                 path: vec![],
                 values: true,
-                labels: vec![(0, Value::text("Grand Total"), 0, None)],
-            });
+                labels: vec![(0, Value::text(text), 0, None)],
+                vi,
+            };
+            if on_rows {
+                lines.extend(val_names.iter().enumerate().map(|(vi, name)| grand(format!("Total {name}"), Some(vi))));
+            } else {
+                lines.push(grand("Grand Total".into(), None));
+            }
         }
     }
     let mut specs: Vec<ColSpec> = Vec::new();
@@ -837,7 +994,10 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
     }
     let mut data_cols: Vec<(usize, Option<usize>)> = Vec::new();
     for (si, _) in specs.iter().enumerate() {
-        if k == 0 {
+        if on_rows {
+            // Each line names its value field; one data column per column item.
+            data_cols.push((si, None));
+        } else if k == 0 {
             if !cols.is_empty() {
                 data_cols.push((si, None));
             }
@@ -852,12 +1012,12 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
     }
 
     let compact = pt.layout == PivotLayout::Compact;
-    let l = if rows.is_empty() && cols.is_empty() {
+    let l = if row_levels == 0 && cols.is_empty() {
         0
     } else if compact {
         1
     } else {
-        rows.len().max(1)
+        row_levels.max(1)
     };
     let mut width = l + data_cols.len();
     if !shown_filters.is_empty() {
@@ -903,14 +1063,19 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
     let val_name = |vi: usize| vals.get(vi).map(|(_, v)| v.name.clone()).unwrap_or_default();
     let headers_on = pt.show_headers;
     let row_header = |g: &mut Grid, r: usize| {
-        if rows.is_empty() || !headers_on {
+        if row_levels == 0 || !headers_on {
             return;
         }
         if compact {
             g.set(r, 0, Value::text("Row Labels"), CellKind::Header, 0, None);
         } else {
-            for (i, f) in row_fields.iter().enumerate() {
-                g.set(r, i, Value::text(f.source_col.as_str()), CellKind::Header, 0, None);
+            // One column per row field, Σ Values ("Values") at its place.
+            let mut names: Vec<&str> = row_fields.iter().map(|f| f.source_col.as_str()).collect();
+            if let Some(p) = vpos {
+                names.insert(p.min(names.len()), "Values");
+            }
+            for (i, name) in names.into_iter().enumerate() {
+                g.set(r, i, Value::text(name), CellKind::Header, 0, None);
             }
         }
     };
@@ -920,8 +1085,11 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
         let r = g.push_row(RowKind::Header)?;
         row_header(&mut g, r);
         for (j, (_, vi)) in data_cols.iter().enumerate() {
-            if let Some(vi) = vi {
-                g.set(r, l + j, Value::text(val_name(*vi)), CellKind::Header, 0, None);
+            match vi {
+                Some(vi) => g.set(r, l + j, Value::text(val_name(*vi)), CellKind::Header, 0, None),
+                // Values on rows, no column field: the one data column is the grand total.
+                None if on_rows => g.set(r, l + j, Value::text("Total"), CellKind::Header, 0, None),
+                None => {}
             }
         }
     } else {
@@ -933,7 +1101,7 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
             let caption = if compact { "Column Labels".to_string() } else { col_fields.first().map(|f| f.source_col.clone()).unwrap_or_default() };
             g.set(cap, l, Value::text(caption), CellKind::Header, 0, None);
         }
-        let levels = cols.len() + usize::from(k > 1);
+        let levels = cols.len() + usize::from(k > 1 && !on_rows);
         let first_level = g.rows.len();
         for _ in 0..levels {
             g.push_row(RowKind::Header)?;
@@ -1048,17 +1216,19 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
                 && (k > 1 || parts.is_empty())
             {
                 parts.push(val_name(*vi));
+            } else if parts.is_empty() {
+                parts.push("Total".into());
             }
             Some(((l + j) as u32, parts.join(" - ")))
         })
         .filter(|_| k > 0)
         .collect();
-    let label_col = if rows.is_empty() {
+    let label_col = if row_levels == 0 {
         None
     } else if compact {
         Some(0)
     } else {
-        Some(rows.len().saturating_sub(1) as u32)
+        Some(row_levels.saturating_sub(1) as u32)
     };
     for line in &lines {
         let rk = match line.kind {
@@ -1082,8 +1252,9 @@ pub fn compute(wb: &Workbook, pt: &PivotTable, pivot_sheet: usize) -> Result<Out
             continue;
         }
         let rp = line.path.as_slice();
-        for (j, (si, vi)) in data_cols.iter().enumerate() {
-            let (Some(spec), Some(vi)) = (specs.get(*si), vi) else { continue };
+        for (j, (si, col_vi)) in data_cols.iter().enumerate() {
+            let line_vi = col_vi.or(line.vi);
+            let (Some(spec), Some(vi)) = (specs.get(*si), &line_vi) else { continue };
             let Some((_, vdef)) = vals.get(*vi) else { continue };
             let cp = spec.path.as_slice();
             let Some(raw) = get(rp, cp, *vi) else { continue };
@@ -1428,3 +1599,17 @@ pub fn clear_output(wb: &mut Workbook, sheet: usize, idx: usize) {
         p.last_range = None;
     }
 }
+
+#[cfg(test)]
+mod fit_tests {
+    use super::data_cols_exceed_sheet;
+
+    #[test]
+    fn column_budget_counts_value_fields_and_grand_total() {
+        assert!(!data_cols_exceed_sheet(64, true, 128));
+        assert!(data_cols_exceed_sheet(64, true, 256));
+        assert!(!data_cols_exceed_sheet(64, false, 256));
+        assert!(!data_cols_exceed_sheet(16_384, false, 0));
+        assert!(data_cols_exceed_sheet(16_385, false, 0));
+    }
+}
diff --git a/crates/engine/src/selection.rs b/crates/engine/src/selection.rs
index 98f0c6c..27418a2 100644
--- a/crates/engine/src/selection.rs
+++ b/crates/engine/src/selection.rs
@@ -43,6 +43,13 @@ impl Selection {
     pub fn is_single_cell(&self) -> bool {
         self.ranges.len() == 1 && self.current().is_single()
     }
+    /// The corner of the current area opposite the anchor: the end that Shift+arrows move.
+    pub fn moving_end(&self) -> CellRef {
+        let r = self.current();
+        let row = if self.anchor.row == r.start.row { r.end.row } else { r.start.row };
+        let col = if self.anchor.col == r.start.col { r.end.col } else { r.start.col };
+        CellRef::new(row, col)
+    }
     /// Extends the current area from the anchor to `to` (Shift+click / Shift+arrows).
     pub fn extend_to(&mut self, to: CellRef) {
         let r = RangeRef::new(self.anchor, to);
diff --git a/crates/engine/src/tests.rs b/crates/engine/src/tests.rs
index 33fdc11..de592f5 100644
--- a/crates/engine/src/tests.rs
+++ b/crates/engine/src/tests.rs
@@ -805,6 +805,46 @@ fn sort_and_filter() {
     assert_eq!(r["hiddenRows"], 1);
 }
 
+/// Top 10 keeps the top or bottom N items or percent, ties at the threshold included.
+#[test]
+fn filter_top10_items_and_percent() {
+    let mut s = s();
+    s.execute("range.setValues", json!({"range": "A1", "values": [["Score"], [5], [1], [9], [3], [9], [7], ["x"]]})).unwrap();
+    s.execute("selection.set", json!({"cell": "A1"})).unwrap();
+    s.execute("data.filter", json!({})).unwrap();
+    // Top 2 items: 9, 9 (the "x" text row is hidden too).
+    let r = s.execute("data.filterBy", json!({"column": "A", "top": {"count": 2}})).unwrap();
+    assert_eq!(r["hiddenRows"], 5);
+    // Bottom 2 items: 1, 3.
+    let r = s.execute("data.filterBy", json!({"column": "A", "top": {"count": 2, "bottom": true}})).unwrap();
+    assert_eq!(r["hiddenRows"], 5);
+    // Top 50 percent of 6 numbers = 3 items; the threshold 7 keeps 9, 9, 7.
+    let r = s.execute("data.filterBy", json!({"column": "A", "top": {"count": 50, "percent": true}})).unwrap();
+    assert_eq!(r["hiddenRows"], 4);
+}
+
+/// Two Top 10 criteria on one column (possible in a native JSON file) each keep their own
+/// cutoff: Top 3 and Bottom 4 of 1..5 keep 3 and 4.
+#[test]
+fn filter_top10_two_criteria_on_one_column() {
+    use gridcraft_model::FilterCriterion;
+    let mut s = s();
+    s.execute("range.setValues", json!({"range": "A1", "values": [["N"], [1], [2], [3], [4], [5]]})).unwrap();
+    s.execute("selection.set", json!({"cell": "A1"})).unwrap();
+    s.execute("data.filter", json!({})).unwrap();
+    let sh = std::sync::Arc::make_mut(&mut s.doc_mut().unwrap().wb).sheet_mut(0).unwrap();
+    if let Some(af) = sh.autofilter.as_mut() {
+        af.criteria = vec![
+            (0, FilterCriterion::Top10 { bottom: false, percent: false, count: 3 }),
+            (0, FilterCriterion::Top10 { bottom: true, percent: false, count: 4 }),
+        ];
+    }
+    s.execute("data.reapply", json!({})).unwrap();
+    let hidden: Vec<u32> = s.active().unwrap().wb.sheet(0).unwrap().rows.iter().filter(|(_, r)| r.hidden).map(|(k, _)| *k).collect();
+    // Rows are 0-based: values 1, 2 and 5 sit on rows 1, 2 and 5.
+    assert_eq!(hidden, vec![1, 2, 5]);
+}
+
 /// Turning the filter on with only the header row selected filters the data below it (#201).
 #[test]
 fn filter_on_a_selected_header_row_covers_the_data_below() {
@@ -1018,6 +1058,48 @@ fn tables_and_structured_refs() {
     assert_eq!(v(&s, "B4"), Value::Number(7.0));
 }
 
+#[test]
+fn structured_refs_to_columns_with_edge_spaces() {
+    let mut s = s();
+    s.execute("range.setValues", json!({"range": "A1", "values": [["Item", "Qty "], ["a", 2], ["b", 3]]})).unwrap();
+    s.execute("insert.table", json!({"range": "A1:B3", "hasHeaders": true})).unwrap();
+    s.execute("table.totalRow", json!({"on": true, "table": "Table1"})).unwrap();
+    assert_eq!(v(&s, "B4"), Value::Number(5.0));
+    for (cell, input) in [
+        ("F1", "=SUM(Table1[Qty ])"),
+        ("F2", "=Table1[[#Totals],[Qty ]]"),
+        ("F3", "=SUBTOTAL(109,Table1[Qty ])"),
+        ("F4", "=SUM(Table1[[Qty ]])"),
+        ("F5", "=SUM(Table1[Qty])"),
+        ("C2", "=Table1[@[Qty ]]*10"),
+    ] {
+        s.execute("cell.set", json!({"cell": cell, "input": input})).unwrap();
+    }
+    let n = Value::Number;
+    assert_eq!([v(&s, "F1"), v(&s, "F2"), v(&s, "F3"), v(&s, "F4")], [n(5.0), n(5.0), n(5.0), n(5.0)]);
+    assert_eq!(v(&s, "F5"), Value::Error(gridcraft_core::CellError::Ref));
+    assert_eq!(v(&s, "C2"), n(20.0));
+    assert_eq!(s.execute("cell.get", json!({"cell": "F3"})).unwrap()["formula"], "=SUBTOTAL(109,Table1[[Qty ]])");
+
+    let r = s.execute("file.saveBytes", json!({"format": "xlsx"})).unwrap();
+    let b64 = r["base64"].as_str().unwrap().to_string();
+    s.execute("file.open", json!({"name": "x.xlsx", "base64": b64})).unwrap();
+    assert_eq!(s.execute("cell.get", json!({"cell": "F3"})).unwrap()["formula"], "=SUBTOTAL(109,Table1[[Qty ]])");
+    assert_eq!([v(&s, "F1"), v(&s, "F2"), v(&s, "F3")], [n(5.0), n(5.0), n(5.0)]);
+fn table_rename_keeps_a_defined_name_with_the_same_name() {
+    let mut s = s();
+    s.execute("range.setValues", json!({"range": "A1", "values": [["Qty"], [7]]})).unwrap();
+    s.execute("cell.set", json!({"cell": "D1", "input": "100"})).unwrap();
+    s.execute("insert.table", json!({"range": "A1:A2", "header": true, "name": "Data"})).unwrap();
+    s.execute("formulas.defineName", json!({"name": "Data", "refersTo": "=Sheet1!$D$1"})).unwrap();
+    s.execute("cell.set", json!({"cell": "E1", "input": "=Data"})).unwrap();
+    s.execute("cell.set", json!({"cell": "F1", "input": "=SUM(Data[Qty])"})).unwrap();
+    s.execute("table.rename", json!({"table": "Data", "name": "Later"})).unwrap();
+    assert_eq!(s.execute("cell.get", json!({"cell": "E1"})).unwrap()["formula"], "=Data");
+    assert_eq!(s.execute("cell.get", json!({"cell": "F1"})).unwrap()["formula"], "=SUM(Later[Qty])");
+    assert_eq!((v(&s, "E1"), v(&s, "F1")), (Value::Number(100.0), Value::Number(7.0)));
+}
+
 #[test]
 fn slicer_filters_table() {
     let mut s = s();
@@ -1170,6 +1252,22 @@ fn insert_and_delete_cells_never_shift_part_of_a_table() {
     assert!(e.to_string().contains("shift cells in a table"), "{e}");
 }
 
+#[test]
+fn table_names_with_a_hyphen_are_rejected() {
+    let mut s = s();
+    s.execute("range.setValues", json!({"range": "A1", "values": [["Qty"], [7]]})).unwrap();
+    let e = s.execute("insert.table", json!({"range": "A1:A2", "header": true, "name": "A-B"})).unwrap_err();
+    assert!(e.to_string().contains("not valid"), "{e}");
+    assert!(s.doc().unwrap().wb.table("A-B").is_none());
+    s.execute("insert.table", json!({"range": "A1:A2", "header": true, "name": "Sales"})).unwrap();
+    let e = s.execute("table.rename", json!({"table": "Sales", "name": "A-B"})).unwrap_err();
+    assert!(e.to_string().contains("not valid"), "{e}");
+    assert!(s.doc().unwrap().wb.table("Sales").is_some());
+    assert!(s.execute("table.rename", json!({"table": "Sales", "name": ".AB"})).is_err());
+    s.execute("table.rename", json!({"table": "Sales", "name": "A_B"})).unwrap();
+    assert!(s.doc().unwrap().wb.table("A_B").is_some());
+}
+
 #[test]
 fn undo_and_redo_keep_the_watch_window_list() {
     // Found by the command-sequence fuzzer: the list lives in the workbook but isn't an edit, so
@@ -1519,6 +1617,65 @@ fn saving_an_opened_semicolon_csv_keeps_semicolons() {
     std::fs::remove_dir_all(dir).unwrap();
 }
 
+/// A typo like `report.cvs` must not quietly write an XLSX under that name and adopt it as the
+/// document's file.
+#[test]
+#[cfg(not(target_arch = "wasm32"))]
+fn saving_to_an_unknown_extension_is_refused() {
+    #[allow(clippy::disallowed_methods)] // native-only test: a unique temp dir name
+    let nonce = std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH).unwrap().as_nanos();
+    let dir = std::env::temp_dir().join(format!("gridcraft-unknown-ext-{}-{nonce}", std::process::id()));
+    std::fs::create_dir(&dir).unwrap();
+    let mut s = s();
+    s.execute("cell.set", json!({"cell": "A1", "input": "1"})).unwrap();
+    for name in ["report.cvs", "report"] {
+        let path = dir.join(name);
+        let e = s.execute("file.save", json!({"path": path})).unwrap_err().to_string();
+        assert!(e.contains(".xlsx"), "{name}: {e}");
+        assert!(!path.exists(), "{name} was written");
+    }
+    let d = s.doc().unwrap();
+    assert!(d.path.is_none());
+    assert!(d.is_dirty());
+    assert!(s.execute("file.saveBytes", json!({"format": "foo"})).is_err());
+    s.execute("file.save", json!({"path": dir.join("report.csv")})).unwrap();
+    std::fs::remove_dir_all(dir).unwrap();
+}
+
+/// An XLSX opened by its content under an unknown extension (`budget.dat`) saves back to its own
+/// file as XLSX; a Save As to another unknown extension is still refused.
+#[test]
+#[cfg(not(target_arch = "wasm32"))]
+fn an_xlsx_opened_under_an_unknown_extension_saves_back_as_xlsx() {
+    #[allow(clippy::disallowed_methods)] // native-only test: a unique temp dir name
+    let nonce = std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH).unwrap().as_nanos();
+    let dir = std::env::temp_dir().join(format!("gridcraft-dat-{}-{nonce}", std::process::id()));
+    std::fs::create_dir(&dir).unwrap();
+    let path = dir.join("budget.dat");
+    let mut src = s();
+    src.execute("cell.set", json!({"cell": "A1", "input": "1"})).unwrap();
+    std::fs::write(&path, crate::io::save_bytes(&src.doc().unwrap().wb, "book.xlsx").unwrap()).unwrap();
+    let mut s = s();
+    s.execute("file.open", json!({"path": path})).unwrap();
+    s.execute("cell.set", json!({"cell": "A1", "input": "2"})).unwrap();
+    s.execute("file.save", json!({})).unwrap();
+    assert!(!s.doc().unwrap().is_dirty());
+    let bytes = std::fs::read(&path).unwrap();
+    assert_eq!(gridcraft_xlsx::sniff(&bytes), gridcraft_xlsx::Format::Xlsx);
+    let (wb, _) = crate::io::open_bytes("book.xlsx", &bytes).unwrap();
+    assert_eq!(wb.active().unwrap().value(CellRef::parse("A1").unwrap()), Value::Number(2.0));
+    assert!(s.execute("file.saveAs", json!({"path": dir.join("copy.foo")})).is_err());
+    assert!(!dir.join("copy.foo").exists());
+    // A text file under an unknown extension opens as CSV: Save doesn't turn it into an XLSX.
+    let notes = dir.join("notes.dat");
+    std::fs::write(&notes, "a,b\r\n").unwrap();
+    s.execute("file.open", json!({"path": notes})).unwrap();
+    s.execute("cell.set", json!({"cell": "A1", "input": "c"})).unwrap();
+    assert!(s.execute("file.save", json!({})).is_err());
+    assert_eq!(std::fs::read_to_string(&notes).unwrap(), "a,b\r\n");
+    std::fs::remove_dir_all(dir).unwrap();
+}
+
 #[test]
 fn validation_formulas_are_relative_and_see_the_new_value() {
     let mut s = s();
@@ -1617,6 +1774,17 @@ fn replacing_a_spilling_formula_clears_its_spill() {
     assert_eq!((v(&s, "A2"), v(&s, "B1")), (Value::Empty, Value::Number(0.0)));
 }
 
+#[test]
+fn clearing_a_spill_past_65536_cells_updates_a_late_dependent() {
+    let mut s = s();
+    s.execute("cell.set", json!({"cell": "A1", "input": "=SEQUENCE(65537)"})).unwrap();
+    s.execute("cell.set", json!({"cell": "C1", "input": "=A65536"})).unwrap();
+    s.execute("cell.set", json!({"cell": "C2", "input": "=A65537"})).unwrap();
+    assert_eq!(v(&s, "C2"), Value::Number(65537.0));
+    s.execute("cell.set", json!({"cell": "A1", "input": "5"})).unwrap();
+    assert_eq!((v(&s, "C1"), v(&s, "C2")), (Value::Number(0.0), Value::Number(0.0)));
+}
+
 #[test]
 fn range_ending_in_index_recalculates() {
     let mut s = s();
@@ -1696,6 +1864,23 @@ fn every_command_survives_empty_params() {
     }
 }
 
+#[test]
+fn non_object_params_do_not_panic_in_wrapper_commands() {
+    // Issue #516.
+    for cmd in ["pageLayout.themeColors", "pageLayout.background", "home.drawBorder"] {
+        for params in [json!([]), json!(5), json!("x"), json!(true)] {
+            let mut s = s();
+            let r = s.execute(cmd, params.clone());
+            assert!(!matches!(r, Err(crate::EngineError::Internal(..))), "{cmd} {params}: {r:?}");
+        }
+    }
+    // A saved script step forwards its params unchanged into the same call.
+    let mut s = s();
+    s.execute("automate.newScript", json!({"name": "bad", "commands": [{"command": "home.drawBorder", "params": []}]})).unwrap();
+    let r = s.execute("automate.runScript", json!({"name": "bad"}));
+    assert!(!matches!(r, Err(crate::EngineError::Internal(..))), "script: {r:?}");
+}
+
 fn fmt_of(s: &Session, a: &str) -> String {
     let wb = &s.doc().unwrap().wb;
     let sh = wb.active().unwrap();
@@ -2505,6 +2690,15 @@ fn fill_series_month_clamps_to_month_end() {
     assert_eq!(v(&s, "A4"), ymd(2026, 4, 15));
 }
 
+#[test]
+fn fill_series_weekday_out_of_range_step_errors() {
+    let mut s = s();
+    s.execute("cell.set", json!({"cell": "A1", "input": "45000"})).unwrap();
+    let r = s.execute("edit.fillSeries", json!({"range": "A1:A2", "direction": "columns", "type": "date", "dateUnit": "weekday", "step": 1e12}));
+    assert!(r.is_err());
+    assert_eq!(v(&s, "A2"), Value::Empty);
+}
+
 #[test]
 fn fill_series_month_leap_year() {
     let s = series_date("2028-01-31", "A1:A3", "month");
@@ -2549,6 +2743,56 @@ fn notes_comments_and_links_survive_a_json_save() {
     assert_eq!(after.cells, before.cells);
 }
 
+/// Insert › Link sorts a target as Excel's dialog does: a sheet reference, a defined name or `#…` is
+/// a place in this document, anything else an existing file or web page. A file saved as a
+/// `location` opens nothing in Excel (#800).
+#[test]
+fn links_to_files_are_saved_as_external_relationships() {
+    use std::io::Read;
+    let mut s = s();
+    s.execute("formulas.defineName", json!({"name": "Price", "refersTo": "=Sheet1!$A$1"})).unwrap();
+    s.execute("insert.table", json!({"range": "F1:G3", "name": "Sales"})).unwrap();
+    s.execute("home.insertSheet", json!({"name": "Q#1"})).unwrap();
+    s.execute("sheet.activate", json!({"sheet": 0})).unwrap();
+    let links = [
+        ("A1", "Source.xlsx", true),
+        ("A2", r"C:\Temp\Book.xlsx", true),
+        ("A3", r"..\Reports\Q1.xlsx", true),
+        ("A4", "Other.xlsx#Sheet1!A2", true),
+        ("A5", "https://example.com/a.xlsx", true),
+        ("A6", "Sheet1!B2", false),
+        ("A7", "#Sheet1!B3", false),
+        ("A8", "Price", false),
+        ("A9", "'Sheet1'!C4:D5", false),
+        ("A10", "Sales", false),
+        ("A11", "'Q#1'!B2", false),
+    ];
+    for (cell, target, _) in links {
+        s.execute("insert.link", json!({"cell": cell, "target": target})).unwrap();
+    }
+    let bytes = gridcraft_xlsx::write_xlsx(&s.doc().unwrap().wb).unwrap();
+    let mut zip = zip::ZipArchive::new(std::io::Cursor::new(bytes.clone())).unwrap();
+    let mut part = |name: &str| {
+        let mut text = String::new();
+        zip.by_name(name).unwrap().read_to_string(&mut text).unwrap();
+        text
+    };
+    let (sheet, rels) = (part("xl/worksheets/sheet1.xml"), part("xl/worksheets/_rels/sheet1.xml.rels"));
+    for (cell, target, external) in links {
+        let file = target.split_once('#').map_or(target, |(f, _)| f);
+        let as_rel = format!("Target=\"{file}\" TargetMode=\"External\"");
+        let as_location = format!("location=\"{}\"", target.trim_start_matches('#'));
+        assert_eq!(rels.contains(&as_rel), external, "{cell} {target}: {rels}");
+        assert_eq!(sheet.contains(&as_location), !external, "{cell} {target}: {sheet}");
+    }
+    assert!(sheet.contains("location=\"Sheet1!A2\""), "{sheet}");
+    let (back, _) = gridcraft_xlsx::read_xlsx(&bytes).unwrap();
+    for (cell, target, external) in links {
+        let h = &back.sheet(0).unwrap().hyperlinks[&CellRef::parse(cell).unwrap()];
+        assert_eq!((h.target.as_str(), h.external), (target.trim_start_matches('#'), external), "{cell}");
+    }
+}
+
 #[test]
 fn vertical_alignment_commands_and_roundtrip() {
     let mut s = s();
@@ -2795,3 +3039,45 @@ fn a_decrypted_workbook_never_overwrites_its_encrypted_original() {
     assert_eq!(std::fs::read(&path).unwrap(), bytes, "the encrypted original is untouched");
     std::fs::remove_dir_all(dir).unwrap();
 }
+
+#[test]
+fn subtotal_109_recalculates_when_row_height_or_autofit_reveals_rows() {
+    let mut s = s();
+    s.execute("range.setValues", json!({"range": "A1", "values": [[1], [2], [4], [8]]})).unwrap();
+    s.execute("cell.set", json!({"cell": "C1", "input": "=SUBTOTAL(109,A1:A4)"})).unwrap();
+    s.execute("home.hideRows", json!({"rows": "2:3"})).unwrap();
+    assert_eq!(v(&s, "C1"), Value::Number(9.0));
+    // A non-zero height unhides the rows (the fuzz found the stale SUBTOTAL).
+    s.execute("home.rowHeight", json!({"rows": "2:3", "height": 60.0})).unwrap();
+    assert_eq!(v(&s, "C1"), Value::Number(15.0));
+    s.execute("home.hideRows", json!({"rows": "2:3"})).unwrap();
+    assert_eq!(v(&s, "C1"), Value::Number(9.0));
+    s.execute("home.autofitRowHeight", json!({"rows": "2:3"})).unwrap();
+    assert_eq!(v(&s, "C1"), Value::Number(15.0));
+fn paste_special_validation_copies_the_rule() {
+    let mut s = s();
+    let ok = |s: &mut Session, cell: &str, input: &str| s.execute("data.validate", json!({"cell": cell, "input": input})).unwrap()["ok"] == true;
+    s.execute("cell.set", json!({"cell": "A1", "input": "5"})).unwrap();
+    s.execute("cell.set", json!({"cell": "C3", "input": "7"})).unwrap();
+    s.execute("data.validation", json!({"range": "A1", "type": "whole", "operator": "greater", "formula1": "0"})).unwrap();
+    s.execute("edit.copy", json!({"range": "A1"})).unwrap();
+    s.execute("edit.pasteSpecial", json!({"what": "formats", "at": "E5"})).unwrap();
+    assert!(ok(&mut s, "E5", "-1"));
+    s.execute("edit.pasteSpecial", json!({"what": "validation", "at": "C3"})).unwrap();
+    assert!(!ok(&mut s, "C3", "-1"));
+    assert!(ok(&mut s, "C3", "1"));
+    assert!(!ok(&mut s, "A1", "-1"));
+    assert_eq!(s.execute("cell.get", json!({"cell": "C3"})).unwrap()["text"], json!("7"));
+}
+
+#[test]
+fn paste_special_validation_moves_relative_references() {
+    let mut s = s();
+    let ok = |s: &mut Session, cell: &str, input: &str| s.execute("data.validate", json!({"cell": cell, "input": input})).unwrap()["ok"] == true;
+    s.execute("cell.set", json!({"cell": "A1", "input": "50"})).unwrap();
+    s.execute("data.validation", json!({"range": "A1", "type": "custom", "formula1": "=A1>10"})).unwrap();
+    s.execute("edit.copy", json!({"range": "A1"})).unwrap();
+    s.execute("edit.pasteSpecial", json!({"what": "validation", "at": "C3"})).unwrap();
+    assert!(!ok(&mut s, "C3", "5"), "the pasted rule checks C3, not A1");
+    assert!(ok(&mut s, "C3", "20"));
+}
diff --git a/crates/engine/tests/custom_view_freeze.rs b/crates/engine/tests/custom_view_freeze.rs
new file mode 100644
index 0000000..e0d6a2d
--- /dev/null
+++ b/crates/engine/tests/custom_view_freeze.rs
@@ -0,0 +1,28 @@
+use gridcraft_engine::Session;
+use serde_json::json;
+
+fn freeze(s: &Session) -> Option<(u32, u32)> {
+    s.doc().unwrap().wb.active().unwrap().freeze
+}
+
+#[test]
+fn showing_a_custom_view_restores_its_frozen_panes() {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("view.freezePanes", json!({"cell": "B2"})).unwrap();
+    s.execute("view.customViews", json!({"save": "Frozen"})).unwrap();
+    s.execute("view.unfreezePanes", json!({})).unwrap();
+    assert_eq!(freeze(&s), None);
+    s.execute("view.customViews", json!({"show": "Frozen"})).unwrap();
+    assert_eq!(freeze(&s), Some((1, 1)));
+}
+
+#[test]
+fn showing_an_unfrozen_custom_view_clears_current_panes() {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("view.customViews", json!({"save": "Plain"})).unwrap();
+    s.execute("view.freezePanes", json!({"cell": "B2"})).unwrap();
+    s.execute("view.customViews", json!({"show": "Plain"})).unwrap();
+    assert_eq!(freeze(&s), None);
+}
diff --git a/crates/engine/tests/ink_roundtrip.rs b/crates/engine/tests/ink_roundtrip.rs
new file mode 100644
index 0000000..bff1b61
--- /dev/null
+++ b/crates/engine/tests/ink_roundtrip.rs
@@ -0,0 +1,135 @@
+//! Native ink remains editable after XLSX saves, including a save after an unrelated cell edit.
+
+use gridcraft_engine::Session;
+use gridcraft_engine::cmd::draw::{ink_points, ink_width};
+use gridcraft_engine::core::{CellRef, Value};
+use gridcraft_engine::model::{Shape, ShapeKind};
+use serde_json::json;
+
+fn workbook() -> Session {
+    let mut session = Session::new();
+    session.new_workbook();
+    session
+}
+
+fn reopen(session: &mut Session) -> Session {
+    let saved = session.execute("file.saveBytes", json!({"format": "xlsx"})).unwrap();
+    let mut reopened = Session::new();
+    reopened.execute("file.open", json!({"name": "ink.xlsx", "base64": saved["base64"]})).unwrap();
+    reopened
+}
+
+fn shapes(session: &Session) -> &[Shape] {
+    &session.doc().unwrap().wb.active().unwrap().shapes
+}
+
+fn assert_anchor(actual: &Shape, expected: &Shape) {
+    assert_eq!(actual.anchor.cell, expected.anchor.cell);
+    assert_eq!(actual.anchor.mode, expected.anchor.mode);
+    for (name, actual, expected) in [
+        ("dx", actual.anchor.dx, expected.anchor.dx),
+        ("dy", actual.anchor.dy, expected.anchor.dy),
+        ("width", actual.anchor.width, expected.anchor.width),
+        ("height", actual.anchor.height, expected.anchor.height),
+    ] {
+        assert!((actual - expected).abs() < 0.001, "anchor {name}: {actual} != {expected}");
+    }
+}
+
+fn assert_ink(actual: &Shape, expected: &Shape) {
+    assert_eq!(actual.kind, ShapeKind::Ink);
+    let actual_points = ink_points(actual);
+    let expected_points = ink_points(expected);
+    assert_eq!(actual_points.len(), expected_points.len());
+    for (actual, expected) in actual_points.iter().zip(&expected_points) {
+        for axis in 0..2 {
+            // DrawingML quantizes coordinates to integer EMUs (9,525 per model unit).
+            assert!((actual[axis] - expected[axis]).abs() < 0.001, "point {actual:?} != {expected:?}");
+        }
+    }
+    assert_eq!(actual.line, expected.line);
+    assert_eq!(ink_width(actual), ink_width(expected));
+    assert_anchor(actual, expected);
+}
+
+#[test]
+fn ink_geometry_and_style_survive_two_saves_and_a_cell_edit() {
+    let mut session = workbook();
+    session
+        .execute("draw.stroke", json!({"points": [[130.5, 45.25], [172.5, 86.25], [151.5, 112.25], [215.5, 59.25]], "color": "#A12BCD", "width": 3}))
+        .unwrap();
+    session
+        .execute("draw.stroke", json!({"points": [[300, 180], [360, 180], [360, 230], [300, 230], [300, 180]], "color": "#16843B", "width": 7}))
+        .unwrap();
+    let expected = shapes(&session).to_vec();
+    assert_eq!(expected.len(), 2);
+
+    for pass in 0..2 {
+        session = reopen(&mut session);
+        assert_eq!(shapes(&session).len(), expected.len());
+        for (actual, expected) in shapes(&session).iter().zip(&expected) {
+            assert_ink(actual, expected);
+        }
+        if pass == 0 {
+            session.execute("cell.set", json!({"cell": "Z30", "input": "42"})).unwrap();
+        }
+    }
+    assert_eq!(session.doc().unwrap().wb.active().unwrap().value(CellRef::parse("Z30").unwrap()), Value::Number(42.0));
+}
+
+#[test]
+fn reopened_ink_can_still_be_converted_to_a_shape() {
+    for (points, expected_kind, expected_name) in [
+        (vec![[100, 100], [200, 100], [200, 180], [100, 180], [100, 100]], ShapeKind::Rectangle, "Rectangle"),
+        (vec![[100, 100], [140, 110], [220, 130]], ShapeKind::Line, "Line"),
+    ] {
+        let mut session = workbook();
+        session.execute("draw.stroke", json!({"points": points, "color": "#A12BCD", "width": 5})).unwrap();
+        let original = shapes(&session)[0].clone();
+        session = reopen(&mut session);
+        let id = shapes(&session)[0].id;
+        let converted = session.execute("draw.inkToShape", json!({"id": id})).unwrap();
+        assert_eq!(converted["kind"], expected_name);
+        let shape = &shapes(&session)[0];
+        assert_eq!(shape.kind, expected_kind);
+        assert_eq!(shape.line, original.line);
+        assert!(shape.text.is_empty());
+        assert_anchor(shape, &original);
+    }
+}
+
+#[test]
+fn ordinary_shape_text_is_not_mistaken_for_ink_points() {
+    let mut session = workbook();
+    session
+        .execute(
+            "insert.shape",
+            json!({"kind": "rectangle", "at": "D6", "width": 120, "height": 60, "fill": "#112233", "line": "#A12BCD", "text": "0.0,0.0;50.0,20.0"}),
+        )
+        .unwrap();
+    let original = shapes(&session)[0].clone();
+    for _ in 0..2 {
+        session = reopen(&mut session);
+        assert_eq!(shapes(&session).len(), 1);
+        let shape = &shapes(&session)[0];
+        assert_eq!(shape.kind, ShapeKind::Rectangle);
+        assert_eq!(shape.text, original.text);
+        assert_eq!(shape.fill, original.fill);
+        assert_eq!(shape.line, original.line);
+        assert_anchor(shape, &original);
+        assert!(session.execute("draw.inkToShape", json!({})).is_err());
+    }
+}
+
+#[test]
+fn horizontal_vertical_and_signed_highlighter_strokes_survive_reopening() {
+    for points in [vec![[25.1, 50.2], [140.3, 50.2]], vec![[40.2, 10.1], [40.2, 100.3]], vec![[-12.3, -4.2], [20.1, 10.2], [80.3, -1.4]]] {
+        let mut session = workbook();
+        session.execute("draw.stroke", json!({"points": points, "color": "#16843B", "width": 12})).unwrap();
+        let expected = shapes(&session)[0].clone();
+        for _ in 0..2 {
+            session = reopen(&mut session);
+            assert_ink(&shapes(&session)[0], &expected);
+        }
+    }
+}
diff --git a/crates/engine/tests/line_count_overflow.rs b/crates/engine/tests/line_count_overflow.rs
new file mode 100644
index 0000000..99fcfea
--- /dev/null
+++ b/crates/engine/tests/line_count_overflow.rs
@@ -0,0 +1,47 @@
+use gridcraft_engine::{EngineError, Session};
+use serde_json::json;
+
+fn new_session() -> Session {
+    let mut session = Session::new();
+    session.new_workbook();
+    session
+}
+
+#[test]
+fn insert_with_an_out_of_range_count_is_a_normal_error() {
+    for (id, key, at) in [("home.insertRows", "rows", "3:3"), ("home.insertColumns", "cols", "C:C")] {
+        let mut session = new_session();
+        let err = session.execute(id, json!({ key: at, "count": u32::MAX })).unwrap_err();
+        assert!(matches!(err, EngineError::BadParams { .. }), "{id}: {err:?}");
+    }
+}
+
+#[test]
+fn insert_after_a_formatted_line_with_an_out_of_range_count_is_a_normal_error() {
+    // A custom size on the preceding line and no cells: the used-range guard has nothing to check.
+    let mut session = new_session();
+    session.execute("home.rowHeight", json!({"rows": "2:2", "height": 30})).unwrap();
+    let err = session.execute("home.insertRows", json!({"rows": "3:3", "count": u32::MAX})).unwrap_err();
+    assert!(matches!(err, EngineError::BadParams { .. }), "{err:?}");
+
+    let mut session = new_session();
+    session.execute("home.columnWidth", json!({"cols": "B:B", "width": 100})).unwrap();
+    let err = session.execute("home.insertColumns", json!({"cols": "C:C", "count": u32::MAX})).unwrap_err();
+    assert!(matches!(err, EngineError::BadParams { .. }), "{err:?}");
+}
+
+#[test]
+fn delete_with_an_out_of_range_count_does_not_panic() {
+    for (id, key, at) in [("home.deleteRows", "rows", "3:3"), ("home.deleteColumns", "cols", "C:C")] {
+        let mut session = new_session();
+        let res = session.execute(id, json!({ key: at, "count": u32::MAX }));
+        assert!(!matches!(res, Err(EngineError::Internal(..))), "{id}: {res:?}");
+    }
+}
+
+#[test]
+fn insert_and_delete_with_a_small_count_still_work() {
+    let mut session = new_session();
+    session.execute("home.insertRows", json!({"rows": "1:1", "count": 3})).unwrap();
+    session.execute("home.deleteRows", json!({"rows": "1:1", "count": 3})).unwrap();
+}
diff --git a/crates/engine/tests/offset_overflow.rs b/crates/engine/tests/offset_overflow.rs
new file mode 100644
index 0000000..de59888
--- /dev/null
+++ b/crates/engine/tests/offset_overflow.rs
@@ -0,0 +1,24 @@
+use gridcraft_core::{CellError, CellRef, Value};
+use gridcraft_engine::Session;
+use serde_json::json;
+
+#[test]
+fn cell_set_offset_extreme_arguments_return_ref() {
+    let mut session = Session::new();
+    session.new_workbook();
+    for formula in [
+        "=OFFSET(B2,1E300,0)",
+        "=OFFSET(B2,0,1E300)",
+        "=OFFSET(B2,0,0,1E300,1)",
+        "=OFFSET(B2,0,0,1,1E300)",
+        "=OFFSET(B2,-1E300,0)",
+        "=OFFSET(B2,0,-1E300)",
+        "=OFFSET(B2,0,0,-1E300,1)",
+        "=OFFSET(B2,0,0,1,-1E300)",
+        "=OFFSET(B2,1E300,0,-1E300,1)",
+        "=OFFSET(B2,0,1E300,1,-1E300)",
+    ] {
+        session.execute("cell.set", json!({"cell": "D1", "input": formula})).unwrap();
+        assert_eq!(session.doc().unwrap().wb.sheet(0).unwrap().value(CellRef::new(0, 3)), Value::Error(CellError::Ref), "{formula}");
+    }
+}
diff --git a/crates/engine/tests/stored_list_shape.rs b/crates/engine/tests/stored_list_shape.rs
new file mode 100644
index 0000000..0d38cd5
--- /dev/null
+++ b/crates/engine/tests/stored_list_shape.rs
@@ -0,0 +1,48 @@
+use gridcraft_engine::Session;
+use serde_json::json;
+
+const NOT_OBJECTS: [&str; 4] = ["\"[1,2]\"", "\"7\"", "\"true\"", "\"\"\"hi\"\"\""];
+
+fn with_name(name: &str, refers_to: &str) -> Session {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("formulas.defineName", json!({"name": name, "refersTo": refers_to})).unwrap();
+    s
+}
+
+#[test]
+fn saving_a_view_works_when_stored_list_is_not_an_object() {
+    for text in NOT_OBJECTS {
+        let mut s = with_name("_sc_custom_views", text);
+        let out = s.execute("view.customViews", json!({"save": "v"})).unwrap();
+        assert!(out.get("v").is_some(), "{text}: {out}");
+    }
+}
+
+#[test]
+fn saving_a_view_keeps_the_keys_of_a_stored_object() {
+    let mut s = with_name("_sc_custom_views", "\"{\"\"a\"\":1}\"");
+    let out = s.execute("view.customViews", json!({"save": "v"})).unwrap();
+    assert!(out.get("a").is_some() && out.get("v").is_some(), "{out}");
+}
+
+#[test]
+fn creating_a_script_works_when_stored_list_is_not_an_object() {
+    for text in NOT_OBJECTS {
+        let mut s = with_name("_sc_scripts", text);
+        s.execute("automate.newScript", json!({"name": "s1", "commands": []})).unwrap();
+        let list = s.execute("automate.allScripts", json!({})).unwrap();
+        assert!(list.to_string().contains("s1"), "{text}: {list}");
+    }
+}
+
+#[test]
+fn stopping_a_recording_works_when_stored_list_is_not_an_object() {
+    for text in NOT_OBJECTS {
+        let mut s = with_name("_sc_scripts", text);
+        s.execute("automate.recordActions", json!({})).unwrap();
+        s.execute("automate.recordActions", json!({"stop": true, "name": "s1"})).unwrap();
+        let list = s.execute("automate.allScripts", json!({})).unwrap();
+        assert!(list.to_string().contains("s1"), "{text}: {list}");
+    }
+}
diff --git a/crates/engine/tests/table_resize_overlap.rs b/crates/engine/tests/table_resize_overlap.rs
new file mode 100644
index 0000000..f8442cc
--- /dev/null
+++ b/crates/engine/tests/table_resize_overlap.rs
@@ -0,0 +1,29 @@
+use gridcraft_engine::Session;
+use serde_json::json;
+
+fn table() -> Session {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("range.setValues", json!({"range":"A1", "values":[["Item", "Qty"], ["x", "7"]]})).unwrap();
+    s.execute("insert.table", json!({"range":"A1:B2", "header":true, "name":"T"})).unwrap();
+    s
+}
+
+fn table_range(s: &Session) -> String {
+    s.doc().unwrap().wb.active().unwrap().tables[0].range.a1()
+}
+
+#[test]
+fn resize_to_disjoint_range_is_rejected_and_keeps_table() {
+    let mut s = table();
+    assert!(s.execute("table.resize", json!({"table":"T", "range":"D1:E2"})).is_err());
+    assert_eq!(table_range(&s), "A1:B2");
+    assert_eq!(s.doc().unwrap().wb.active().unwrap().tables[0].columns[1].name, "Qty");
+}
+
+#[test]
+fn resize_to_overlapping_range_still_works() {
+    let mut s = table();
+    s.execute("table.resize", json!({"table":"T", "range":"B1:C2"})).unwrap();
+    assert_eq!(table_range(&s), "B1:C2");
+}
diff --git a/crates/engine/tests/table_total_row_last_row.rs b/crates/engine/tests/table_total_row_last_row.rs
new file mode 100644
index 0000000..eb1bd3d
--- /dev/null
+++ b/crates/engine/tests/table_total_row_last_row.rs
@@ -0,0 +1,34 @@
+use gridcraft_core::{CellRef, MAX_ROWS};
+use gridcraft_engine::Session;
+use serde_json::json;
+
+fn refused(range: &str) {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("insert.table", json!({"range": range, "header": true})).unwrap();
+    let before = s.doc().unwrap().wb.active().unwrap().tables[0].clone();
+    assert!(s.execute("table.totalRow", json!({"on": true, "table": &before.name})).is_err(), "{range}");
+    let sh = s.doc().unwrap().wb.active().unwrap();
+    assert_eq!(sh.tables[0].range, before.range, "{range}");
+    assert_eq!(sh.tables[0].range.end.row, MAX_ROWS - 1, "{range}");
+    assert!(!sh.tables[0].totals_row, "{range}");
+    assert!(sh.value(CellRef::new(MAX_ROWS, 0)).is_empty(), "{range}");
+}
+
+#[test]
+fn total_row_is_refused_on_a_table_ending_at_the_last_worksheet_row() {
+    refused("A1048575:B1048576");
+    refused("A1048576:B1048576");
+}
+
+#[test]
+fn total_row_still_grows_an_ordinary_table() {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("range.setValues", json!({"range": "A1", "values": [["Item", "Amount"], ["a", 2], ["b", 3]]})).unwrap();
+    s.execute("insert.table", json!({"range": "A1:B3", "header": true})).unwrap();
+    s.execute("table.totalRow", json!({"on": true, "table": "Table1"})).unwrap();
+    let t = &s.doc().unwrap().wb.active().unwrap().tables[0];
+    assert!(t.totals_row);
+    assert_eq!(t.range.end.row, 3);
+}
diff --git a/crates/formula/src/adjust.rs b/crates/formula/src/adjust.rs
index 6f01e05..d4881aa 100644
--- a/crates/formula/src/adjust.rs
+++ b/crates/formula/src/adjust.rs
@@ -264,11 +264,10 @@ pub fn rename_sheet(e: Expr, old: &str, new: &str) -> Expr {
             }
             Expr::Ref(r)
         }
-        // Sheet-qualified defined name `Old!MyName` is stored as one string.
+        // Sheet-qualified defined name `Old!MyName` is stored as one string, with the bare sheet name as the parser
+        // stores it (the printer adds the quotes).
         Expr::Name(n) => match n.split_at_checked(old.len()) {
-            Some((head, rest)) if head.eq_ignore_ascii_case(old) && rest.starts_with('!') => {
-                Expr::Name(format!("{}{rest}", crate::printer::quote_sheet(new)))
-            }
+            Some((head, rest)) if head.eq_ignore_ascii_case(old) && rest.starts_with('!') => Expr::Name(format!("{new}{rest}")),
             _ => Expr::Name(n),
         },
         other => other,
diff --git a/crates/formula/src/parser.rs b/crates/formula/src/parser.rs
index 4fd3b7b..3ea9708 100644
--- a/crates/formula/src/parser.rs
+++ b/crates/formula/src/parser.rs
@@ -50,8 +50,9 @@ fn significant_spaces(toks: Vec<Token>) -> Vec<Token> {
     let mut out: Vec<Token> = Vec::with_capacity(toks.len());
     for (i, t) in toks.iter().enumerate() {
         if t.tok == Tok::Space {
-            let prev_end = out.last().is_some_and(|p| matches!(p.tok, Tok::Word(_) | Tok::RParen | Tok::Struct(_)));
-            let next_start = toks.get(i + 1).is_some_and(|n| matches!(n.tok, Tok::Word(_) | Tok::Sheet(..) | Tok::LParen | Tok::Func(_)));
+            let prev_end = out.last().is_some_and(|p| matches!(p.tok, Tok::Word(_) | Tok::RParen | Tok::Struct(_) | Tok::Error(_)));
+            let next_start =
+                toks.get(i + 1).is_some_and(|n| matches!(n.tok, Tok::Word(_) | Tok::Sheet(..) | Tok::LParen | Tok::Func(_) | Tok::Error(_)));
             if prev_end && next_start {
                 out.push(t.clone());
             }
@@ -88,15 +89,19 @@ fn word_is_cell(w: &str) -> Option<Anchor> {
     Some(Anchor { row, col, row_abs, col_abs })
 }
 
-/// `_xlfn.XLOOKUP` → `XLOOKUP`.
+/// `_xlfn.XLOOKUP` → `XLOOKUP`. `_xludf.` is kept (`_xludf.SUM`): it marks a user-defined
+/// function, never the built-in of the same name, and files need it back.
 pub fn normalize_function_name(name: &str) -> String {
     let u = name.to_ascii_uppercase();
-    for p in ["_XLFN._XLWS.", "_XLFN.", "_XLWS.", "_XLUDF."] {
+    for p in ["_XLFN._XLWS.", "_XLFN.", "_XLWS."] {
         if let Some(r) = u.strip_prefix(p) {
             return r.to_string();
         }
     }
-    u
+    match u.strip_prefix("_XLUDF.") {
+        Some(r) => format!("_xludf.{r}"),
+        None => u,
+    }
 }
 
 impl Parser {
@@ -357,6 +362,10 @@ impl Parser {
         if w.chars().next().is_some_and(|c| c.is_ascii_digit()) {
             return Err(self.err(format!("unexpected `{w}`")));
         }
+        // A function passed by name is saved as `_xleta.SUM`.
+        if let Some(f) = w.get(..7).filter(|p| p.eq_ignore_ascii_case("_xleta.")).and_then(|_| w.get(7..)) {
+            return Ok(Expr::Name(f.to_ascii_uppercase()));
+        }
         Ok(Expr::Name(w.to_string()))
     }
 
@@ -417,6 +426,9 @@ fn combine(op: BinOp, lhs: Expr, rhs: Expr) -> Expr {
 pub fn parse_struct(table: &str, body: &str) -> Result<StructRef, String> {
     let mut specifiers = Vec::new();
     let mut cols: Vec<String> = Vec::new();
+    // Spaces at the edges of a column name are part of it (`Table1[Qty ]` names `Qty `), so the
+    // untrimmed body is what a lone column is read from.
+    let raw = body;
     let body = body.trim();
     let unescape = |s: &str| {
         let mut out = String::new();
@@ -468,7 +480,7 @@ pub fn parse_struct(table: &str, body: &str) -> Result<StructRef, String> {
         } else if let Some(i) = item(body) {
             specifiers.push(i);
         } else if !body.is_empty() {
-            cols.push(column(body)?);
+            cols.push(column(raw)?);
         }
     } else {
         // [[#Headers],[Col1]:[Col3]], [[#This Row],[Col 1]] or [[#This Row],Col1]
diff --git a/crates/formula/src/printer.rs b/crates/formula/src/printer.rs
index a63599b..3975a7c 100644
--- a/crates/formula/src/printer.rs
+++ b/crates/formula/src/printer.rs
@@ -91,6 +91,16 @@ fn range_r1c1(r: &Reference, at: CellRef, sep: &str) -> String {
 }
 
 pub fn struct_ref(s: &StructRef) -> String {
+    write_struct_ref(s, true)
+}
+
+/// Structured reference as files spell it: `[@Col]` is only Excel's display shorthand, files
+/// hold `[[#This Row],[Col]]` (and `[#This Row]` for `[@]`).
+pub fn struct_ref_file(s: &StructRef) -> String {
+    write_struct_ref(s, false)
+}
+
+fn write_struct_ref(s: &StructRef, at_shorthand: bool) -> String {
     let esc = |c: &str| c.replace('\'', "''").replace('[', "'[").replace(']', "']").replace('#', "'#");
     let item = |i: &StructItem| match i {
         StructItem::All => "#All",
@@ -99,7 +109,7 @@ pub fn struct_ref(s: &StructRef) -> String {
         StructItem::Totals => "#Totals",
         StructItem::ThisRow => "#This Row",
     };
-    let this_row = s.specifiers == [StructItem::ThisRow];
+    let this_row = at_shorthand && s.specifiers == [StructItem::ThisRow];
     let mut out = s.table.clone();
     let simple_col = |c: &str| !c.chars().any(|ch| matches!(ch, ' ' | '[' | ']' | '#' | '\'' | ',' | ':'));
     match (&s.col_start, &s.col_end) {
@@ -109,7 +119,12 @@ pub fn struct_ref(s: &StructRef) -> String {
             let _ = write!(out, "[{}]", s.specifiers.first().map(item).unwrap_or(""));
         }
         (Some(c), None) if s.specifiers.is_empty() => {
-            let _ = write!(out, "[{}]", esc(c));
+            // Excel writes a name with spaces at its edges in the double-bracket form.
+            if c.trim() == c {
+                let _ = write!(out, "[{}]", esc(c));
+            } else {
+                let _ = write!(out, "[[{}]]", esc(c));
+            }
         }
         (Some(c), None) if this_row => {
             if simple_col(c) {
@@ -178,7 +193,15 @@ fn write_expr(s: &mut String, e: &Expr, r1c1: Option<CellRef>) {
             Some(at) => s.push_str(&reference_r1c1(r, at)),
             None => s.push_str(&reference_a1(r)),
         },
-        Expr::Name(n) => s.push_str(n),
+        Expr::Name(n) => match n.rsplit_once('!') {
+            // A sheet-qualified name is stored with the bare sheet name (`My Sheet!Total`): quote it so it parses back.
+            Some((sheet, name)) => {
+                s.push_str(&quote_sheet(sheet));
+                s.push('!');
+                s.push_str(name);
+            }
+            _ => s.push_str(n),
+        },
         Expr::Struct(st) => s.push_str(&struct_ref(st)),
         Expr::Unary(op, x) => match op {
             UnOp::Neg => {
@@ -224,10 +247,20 @@ fn write_expr(s: &mut String, e: &Expr, r1c1: Option<CellRef>) {
                 }
             },
         },
-        Expr::Binary(op, a, b) => {
-            write_expr(s, a, r1c1);
-            s.push_str(op.symbol());
-            write_expr(s, b, r1c1);
+        Expr::Binary(..) => {
+            // Walk the left spine iteratively: a flat chain such as `1+1+1+...` parses into a
+            // tree one level deeper per operator, and recursing on it could exhaust the stack.
+            let mut rest: Vec<(&BinOp, &Expr)> = Vec::new();
+            let mut first = e;
+            while let Expr::Binary(op, a, b) = first {
+                rest.push((op, b));
+                first = a;
+            }
+            write_expr(s, first, r1c1);
+            for (op, right) in rest.into_iter().rev() {
+                s.push_str(op.symbol());
+                write_expr(s, right, r1c1);
+            }
         }
         Expr::Call(name, args) => {
             s.push_str(name);
diff --git a/crates/formula/src/tests.rs b/crates/formula/src/tests.rs
index d3dd4c2..c8359b1 100644
--- a/crates/formula/src/tests.rs
+++ b/crates/formula/src/tests.rs
@@ -5,6 +5,26 @@ fn rt(src: &str) -> String {
     print(&parse(src).unwrap_or_else(|e| panic!("{src}: {e}")))
 }
 
+#[test]
+fn quoted_sheet_qualified_name_keeps_quotes() {
+    assert_eq!(rt("'My Sheet'!Total"), "'My Sheet'!Total");
+    assert_eq!(rt("'Data'!Total"), "Data!Total");
+    assert_eq!(rt("'It''s'!Total+1"), "'It''s'!Total+1");
+fn intersection_with_deleted_operand_reparses() {
+    // Deleting the columns of an intersection operand prints `A1:B2 #REF!`; that text must parse back.
+    assert_eq!(rt("A1:B2 #REF!"), "A1:B2 #REF!");
+    assert_eq!(rt("#REF! A1:B2"), "#REF! A1:B2");
+    assert_eq!(parse("A1:B2 #REF!"), parse("A1:B2 (#REF!)").map(|e| strip_paren(&e)));
+}
+
+fn strip_paren(e: &Expr) -> Expr {
+    match e {
+        Expr::Binary(op, a, b) => Expr::Binary(*op, Box::new(strip_paren(a)), Box::new(strip_paren(b))),
+        Expr::Paren(x) => strip_paren(x),
+        other => other.clone(),
+    }
+}
+
 #[test]
 fn roundtrips() {
     for f in [
@@ -48,6 +68,8 @@ fn normalises() {
     assert_eq!(rt("=sum(a1:b2)"), "SUM(A1:B2)");
     assert_eq!(rt("= 1 + 2"), "1+2");
     assert_eq!(rt("_xlfn.XLOOKUP(1,A:A,B:B)"), "XLOOKUP(1,A:A,B:B)");
+    assert_eq!(rt("_xlfn.GROUPBY(A1:A3,B1:B3,_xleta.SUM)"), "GROUPBY(A1:A3,B1:B3,SUM)");
+    assert_eq!(rt("_XLUDF.concat(\"a\",\"b\")"), "_xludf.CONCAT(\"a\",\"b\")");
     assert_eq!(rt("true"), "TRUE");
     assert_eq!(rt("'Sheet1'!A1"), "Sheet1!A1");
 }
@@ -183,6 +205,10 @@ fn rename_sheet_updates_qualified_names() {
     assert_eq!(print(&rename_sheet(e, "data", "Numbers")), "Numbers!MyName+MyName+Other!MyName");
     let e = parse("Data!MyName").unwrap();
     assert_eq!(print(&rename_sheet(e, "Data", "New Name")), "'New Name'!MyName");
+    // Stored bare, like a parsed name, so the evaluator finds the sheet and a second rename still matches.
+    let e = rename_sheet(parse("Data!MyName").unwrap(), "Data", "It's");
+    assert_eq!(e, Expr::Name("It's!MyName".into()));
+    assert_eq!(print(&rename_sheet(e, "It's", "Totals")), "Totals!MyName");
 }
 
 #[test]
@@ -248,6 +274,20 @@ fn unbracketed_this_row_column() {
     }
 }
 
+#[test]
+fn struct_column_keeps_edge_spaces() {
+    // The spaces are part of the column name: `Table1[Qty ]` names `Qty `, never `Qty`.
+    let Expr::Struct(s) = parse("Table1[Qty ]").unwrap() else { panic!() };
+    assert_eq!(s.col_start.as_deref(), Some("Qty "));
+    let Expr::Struct(s) = parse("Table1[ Qty]").unwrap() else { panic!() };
+    assert_eq!(s.col_start.as_deref(), Some(" Qty"));
+    // Excel writes such a column in the double-bracket form.
+    assert_eq!(rt("Table1[Qty ]"), "Table1[[Qty ]]");
+    for f in ["Table1[[Qty ]]", "Table1[[ Sum for Q2 ]]", "Table1[[#Totals],[Qty ]]", "Table1[@[Qty ]]", "Table1[Unit Price]"] {
+        assert_eq!(rt(f), f);
+    }
+}
+
 #[test]
 fn trim_references() {
     for f in [
@@ -301,3 +341,25 @@ fn trim_references_adjust() {
     let refs: Vec<String> = parse("SUM(Sheet2!A1:.B5)").unwrap().references().iter().map(|r| printer::reference_a1(r)).collect();
     assert_eq!(refs, ["Sheet2!A1:B5"]);
 }
+
+#[test]
+fn prints_long_flat_chain_without_deep_recursion() {
+    // Small stack: a recursive printer overflows long before 20000 levels.
+    let handle = std::thread::Builder::new()
+        .stack_size(256 * 1024)
+        .spawn(|| {
+            let mut e = Expr::Number(1.0);
+            for _ in 0..20000 {
+                e = Expr::Binary(BinOp::Add, Box::new(e), Box::new(Expr::Number(1.0)));
+            }
+            let text = print(&e);
+            let r1c1 = print_r1c1(&e, gridcraft_core::CellRef { row: 0, col: 0 });
+            // Dropping the deep tree recurses; leak it so only the printer is under test.
+            std::mem::forget(e);
+            (text, r1c1)
+        })
+        .expect("spawn");
+    let (text, r1c1) = handle.join().expect("printer must not overflow the stack");
+    assert_eq!(text, vec!["1"; 20001].join("+"));
+    assert_eq!(r1c1, text);
+}
diff --git a/crates/functions/src/criteria.rs b/crates/functions/src/criteria.rs
index 20410c8..2b4c488 100644
--- a/crates/functions/src/criteria.rs
+++ b/crates/functions/src/criteria.rs
@@ -5,6 +5,10 @@ use std::cmp::Ordering;
 use gridcraft_core::parse::parse_number_text;
 use gridcraft_core::{CellError, Value, compare_numbers, compare_text};
 
+/// Longest text criterion COUNTIF and its relatives accept, in UTF-16 code units as Excel
+/// counts them (😀 is two units); a longer one is `#VALUE!`.
+const MAX_CRITERION_UTF16_UNITS: usize = 255;
+
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 enum Op {
     Eq,
@@ -22,6 +26,15 @@ enum Operand {
     Error(CellError),
     /// Text (lower-cased chars kept for wildcard matching).
     Text(String),
+    /// A criterion cut to its first 255 UTF-16 units in the middle of a surrogate pair: the
+    /// complete characters before the cut, followed (in Excel) by a lone high surrogate.
+    ///
+    /// No cell text holds a lone surrogate, so `=` matches nothing and `<>` everything, as
+    /// Excel gives 0 for SUMIFS with a criterion of 128 emoji. For `<`, `<=`, `>` and `>=` the
+    /// criterion sorts just above the kept text: a cell matches `>`/`>=` when it sorts above
+    /// that text, and `<`/`<=` otherwise. This is an approximation (Excel wasn't checked) and
+    /// only matters for comparison criteria over 255 units.
+    CutText(String),
     /// Nothing after the operator (`"="`, `"<>"`) or an empty criterion.
     Blank,
 }
@@ -48,25 +61,52 @@ impl Criterion {
         }
     }
 
-    fn parse_text(t: &str) -> Criterion {
-        let (op, rest) = if let Some(r) = t.strip_prefix(">=") {
-            (Op::Ge, r)
-        } else if let Some(r) = t.strip_prefix("<=") {
-            (Op::Le, r)
-        } else if let Some(r) = t.strip_prefix("<>") {
-            (Op::Ne, r)
-        } else if let Some(r) = t.strip_prefix('=') {
-            (Op::Eq, r)
-        } else if let Some(r) = t.strip_prefix('>') {
-            (Op::Gt, r)
-        } else if let Some(r) = t.strip_prefix('<') {
-            (Op::Lt, r)
-        } else {
-            if t.is_empty() {
-                return Criterion { op: Op::Eq, operand: Operand::Blank, bare_empty: true };
+    /// Parses the criteria argument of COUNTIF, SUMIF, AVERAGEIF and the single-pair *IFS
+    /// functions: like `parse`, but text longer than 255 UTF-16 code units is `#VALUE!`, as in
+    /// Excel (checked on Excel 2016 and Microsoft 365: `"a"×254 & "😀"` is 255 characters but
+    /// 256 units, and is `#VALUE!`).
+    pub(crate) fn parse_arg(v: &Value) -> Result<Criterion, CellError> {
+        match v {
+            Value::Array(a) => Criterion::parse_arg(a.data.first().unwrap_or(&Value::Empty)),
+            // A UTF-8 string has at least as many bytes as UTF-16 units, so short text skips the count.
+            Value::Text(t) if t.len() > MAX_CRITERION_UTF16_UNITS && t.encode_utf16().nth(MAX_CRITERION_UTF16_UNITS).is_some() => {
+                Err(CellError::Value)
             }
-            (Op::Eq, t)
-        };
+            other => Ok(Criterion::parse(other)),
+        }
+    }
+
+    /// Parses a criteria argument of an *IFS function with two or more criteria pairs. Excel
+    /// doesn't reject a longer text criterion there: it matches its first 255 UTF-16 code units
+    /// (checked on Excel 2016 and Microsoft 365 with COUNTIFS, SUMIFS, AVERAGEIFS, MAXIFS and
+    /// MINIFS). A cut through a surrogate pair matches nothing; see `Operand::CutText`.
+    pub(crate) fn parse_arg_truncated(v: &Value) -> Criterion {
+        match v {
+            Value::Array(a) => Criterion::parse_arg_truncated(a.data.first().unwrap_or(&Value::Empty)),
+            Value::Text(t) if t.len() > MAX_CRITERION_UTF16_UNITS => {
+                let mut units = 0;
+                for (i, c) in t.char_indices() {
+                    if units + c.len_utf16() > MAX_CRITERION_UTF16_UNITS {
+                        if units == MAX_CRITERION_UTF16_UNITS {
+                            return Criterion::parse_text(&t[..i]);
+                        }
+                        // The cut falls between the two halves of `c`.
+                        let (op, rest) = split_op(&t[..i]);
+                        return Criterion { op, operand: Operand::CutText(rest.to_string()), bare_empty: false };
+                    }
+                    units += c.len_utf16();
+                }
+                Criterion::parse_text(t)
+            }
+            other => Criterion::parse(other),
+        }
+    }
+
+    fn parse_text(t: &str) -> Criterion {
+        if t.is_empty() {
+            return Criterion { op: Op::Eq, operand: Operand::Blank, bare_empty: true };
+        }
+        let (op, rest) = split_op(t);
         let operand = if rest.is_empty() {
             Operand::Blank
         } else if let Some(n) = parse_number_text(rest) {
@@ -140,10 +180,35 @@ impl Criterion {
                     _ => false,
                 },
             },
+            Operand::CutText(kept) => match self.op {
+                Op::Eq => false,
+                Op::Ne => true,
+                Op::Lt | Op::Le => matches!(&v, Value::Text(t) if compare_text(t, kept) != Ordering::Greater),
+                Op::Gt | Op::Ge => matches!(&v, Value::Text(t) if compare_text(t, kept) == Ordering::Greater),
+            },
         }
     }
 }
 
+/// Splits a leading comparison operator (`=` when there is none) off a text criterion.
+fn split_op(t: &str) -> (Op, &str) {
+    if let Some(r) = t.strip_prefix(">=") {
+        (Op::Ge, r)
+    } else if let Some(r) = t.strip_prefix("<=") {
+        (Op::Le, r)
+    } else if let Some(r) = t.strip_prefix("<>") {
+        (Op::Ne, r)
+    } else if let Some(r) = t.strip_prefix('=') {
+        (Op::Eq, r)
+    } else if let Some(r) = t.strip_prefix('>') {
+        (Op::Gt, r)
+    } else if let Some(r) = t.strip_prefix('<') {
+        (Op::Lt, r)
+    } else {
+        (Op::Eq, t)
+    }
+}
+
 fn cmp_op(op: Op, o: Ordering) -> bool {
     match op {
         Op::Eq => o == Ordering::Equal,
diff --git a/crates/functions/src/database.rs b/crates/functions/src/database.rs
index 38e3729..67132e9 100644
--- a/crates/functions/src/database.rs
+++ b/crates/functions/src/database.rs
@@ -4,7 +4,9 @@
 //! The database and the criteria are arrays whose first row holds column labels. Each criteria
 //! row is a set of conditions that must all hold (AND); a record matches when any criteria row
 //! holds (OR). An empty criteria cell matches anything. Plain text conditions match values that
-//! begin with the text, as in Excel's advanced filter.
+//! begin with the text, as in Excel's advanced filter, so an empty string matches any text. A
+//! formula under a label that names no field is a computed criterion, which the host evaluates
+//! for each record ([`Ctx::computed_criterion`]).
 
 use std::borrow::Cow;
 
@@ -49,7 +51,6 @@ fn field_index(db: &Array, a: &[Arg]) -> R<Option<usize>> {
 fn cell_criterion(v: &Value) -> Option<Criterion> {
     match v {
         Value::Empty => None,
-        Value::Text(t) if t.is_empty() => None,
         Value::Text(t) => {
             let s: &str = t;
             let has_op = s.starts_with(['=', '<', '>']);
@@ -65,9 +66,10 @@ fn cell_criterion(v: &Value) -> Option<Criterion> {
 }
 
 /// Rows (1-based within the database, excluding the header) of matching records.
-fn matching_records(db: &Array, crit: &Array) -> Vec<usize> {
-    // Per criteria row: list of (database column or None when the label is unknown, criterion).
-    let mut rows: Vec<Vec<(Option<usize>, Criterion)>> = Vec::new();
+fn matching_records(db: &Array, crit: &Array, ctx: &mut dyn Ctx) -> Vec<usize> {
+    // Per criteria row: its index and a list of (criteria column, database column or None when
+    // the label is unknown, criterion).
+    let mut rows: Vec<(usize, Vec<(usize, Option<usize>, Criterion)>)> = Vec::new();
     for r in 1..crit.rows {
         let mut conds = Vec::new();
         for c in 0..crit.cols {
@@ -78,18 +80,20 @@ fn matching_records(db: &Array, crit: &Array) -> Vec<usize> {
                 Some(Value::Number(n)) => find_column(db, &gridcraft_core::number_to_text(*n)),
                 _ => None,
             };
-            conds.push((col, cr));
+            conds.push((c, col, cr));
         }
-        rows.push(conds);
+        rows.push((r, conds));
     }
     let all_match = rows.is_empty();
     (1..db.rows)
-        .filter(|&r| {
+        .filter(|&rec| {
             all_match
-                || rows.iter().any(|conds| {
-                    conds.iter().all(|(col, cr)| match col {
-                        Some(c) => cr.matches(db.get(r, *c).unwrap_or(&Value::Empty)),
-                        None => false,
+                || rows.iter().any(|(r, conds)| {
+                    conds.iter().all(|(c, col, cr)| match col {
+                        Some(f) => cr.matches(db.get(rec, *f).unwrap_or(&Value::Empty)),
+                        // Under a label that names no field, only a formula (a computed
+                        // criterion) can hold.
+                        None => ctx.computed_criterion(*r, *c, db, rec).unwrap_or(false),
                     })
                 })
         })
@@ -102,7 +106,7 @@ struct Selection<'a> {
     records: Vec<usize>,
 }
 
-fn select(a: &[Arg]) -> R<Selection<'_>> {
+fn select<'a>(a: &'a [Arg], ctx: &mut dyn Ctx) -> R<Selection<'a>> {
     let dbv = &a.first().ok_or(CellError::Value)?.value;
     let critv = &a.get(2).ok_or(CellError::Value)?.value;
     if let Value::Error(e) = dbv {
@@ -114,31 +118,31 @@ fn select(a: &[Arg]) -> R<Selection<'_>> {
     let db = as_array(dbv);
     let crit = as_array(critv);
     let field = field_index(&db, a)?;
-    let records = matching_records(&db, &crit);
+    let records = matching_records(&db, &crit, ctx);
     Ok(Selection { db, field, records })
 }
 
 /// Numbers of the field among matching records (field required).
-fn field_numbers(a: &[Arg]) -> R<Vec<f64>> {
-    let s = select(a)?;
+fn field_numbers(a: &[Arg], c: &mut dyn Ctx) -> R<Vec<f64>> {
+    let s = select(a, c)?;
     let f = s.field.ok_or(CellError::Value)?;
     Ok(s.records.iter().filter_map(|&r| s.db.get(r, f).and_then(Value::as_f64)).collect())
 }
 
-fn dsum(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    num_val(field_numbers(a)?.iter().sum())
+fn dsum(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    num_val(field_numbers(a, c)?.iter().sum())
 }
 
-fn daverage(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let v = field_numbers(a)?;
+fn daverage(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let v = field_numbers(a, c)?;
     if v.is_empty() {
         return Err(CellError::Div0);
     }
     num_val(v.iter().sum::<f64>() / v.len() as f64)
 }
 
-fn dcount(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let s = select(a)?;
+fn dcount(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let s = select(a, c)?;
     let n = match s.field {
         Some(f) => s.records.iter().filter(|&&r| matches!(s.db.get(r, f), Some(Value::Number(_)))).count(),
         None => s.records.len(),
@@ -146,8 +150,8 @@ fn dcount(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     num_val(n as f64)
 }
 
-fn dcounta(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let s = select(a)?;
+fn dcounta(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let s = select(a, c)?;
     let n = match s.field {
         Some(f) => s.records.iter().filter(|&&r| !matches!(s.db.get(r, f), None | Some(Value::Empty))).count(),
         None => s.records.len(),
@@ -155,28 +159,31 @@ fn dcounta(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     num_val(n as f64)
 }
 
-fn dget(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let s = select(a)?;
+fn dget(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let s = select(a, c)?;
     let f = s.field.ok_or(CellError::Value)?;
-    match s.records.as_slice() {
-        [] => Err(CellError::Value),
-        [r] => Ok(s.db.get(*r, f).cloned().unwrap_or(Value::Empty)),
+    // Records whose field is blank (or "") don't count, as in Excel.
+    let mut found =
+        s.records.iter().filter_map(|&r| s.db.get(r, f)).filter(|v| !matches!(v, Value::Empty) && !matches!(v, Value::Text(t) if t.is_empty()));
+    match (found.next(), found.next()) {
+        (None, _) => Err(CellError::Value),
+        (Some(v), None) => Ok(v.clone()),
         _ => Err(CellError::Num),
     }
 }
 
-fn dmax(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let v = field_numbers(a)?;
+fn dmax(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let v = field_numbers(a, c)?;
     num_val(v.iter().copied().reduce(f64::max).unwrap_or(0.0))
 }
 
-fn dmin(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let v = field_numbers(a)?;
+fn dmin(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let v = field_numbers(a, c)?;
     num_val(v.iter().copied().reduce(f64::min).unwrap_or(0.0))
 }
 
-fn dproduct(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    let v = field_numbers(a)?;
+fn dproduct(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    let v = field_numbers(a, c)?;
     if v.is_empty() {
         return num_val(0.0);
     }
@@ -194,20 +201,20 @@ fn variance(v: &[f64], sample: bool) -> R<f64> {
     Ok(ss / if sample { n - 1.0 } else { n })
 }
 
-fn dvar(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    num_val(variance(&field_numbers(a)?, true)?)
+fn dvar(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    num_val(variance(&field_numbers(a, c)?, true)?)
 }
 
-fn dvarp(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    num_val(variance(&field_numbers(a)?, false)?)
+fn dvarp(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    num_val(variance(&field_numbers(a, c)?, false)?)
 }
 
-fn dstdev(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    num_val(variance(&field_numbers(a)?, true)?.sqrt())
+fn dstdev(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    num_val(variance(&field_numbers(a, c)?, true)?.sqrt())
 }
 
-fn dstdevp(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
-    num_val(variance(&field_numbers(a)?, false)?.sqrt())
+fn dstdevp(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
+    num_val(variance(&field_numbers(a, c)?, false)?.sqrt())
 }
 
 pub(crate) fn specs() -> Vec<FnSpec> {
@@ -371,4 +378,69 @@ mod tests {
         is_err(ev("DSUM", vec![e(CellError::Ref), t("Yield"), rf(c("=Cherry"))]), CellError::Ref);
         close(ev("DCOUNTA", vec![rf(db()), empty(), rf(c("=Pear"))]), 2.0);
     }
+
+    /// Expected results are Excel's, from Apache POI's `DGet.xls` (rows 74-86).
+    #[test]
+    fn empty_string_criterion() {
+        let db = arr(vec![
+            vec![tv("Index"), tv("Value")],
+            vec![tv("a"), tv("=")],
+            vec![tv("b"), Value::Empty],
+            vec![tv("c"), tv("")],
+            vec![tv("d"), tv(" ")],
+            vec![tv("f"), Value::Error(CellError::Value)],
+            vec![tv("h"), tv("abc")],
+            vec![tv("i"), nv(0.0)],
+        ]);
+        let get = |index: &str| {
+            let crit = arr(vec![vec![tv("Index"), tv("Value")], vec![tv(index), tv("")]]);
+            ev("DGET", vec![rf(db.clone()), t("Index"), rf(crit)])
+        };
+        // Like any plain text, "" is a "begins with" pattern: it matches every text value.
+        is_text(get("c"), "c");
+        is_text(get("h"), "h");
+        is_err(get("b"), CellError::Value);
+        is_err(get("i"), CellError::Value);
+        is_err(get("f"), CellError::Value);
+        let all = arr(vec![vec![tv("Value")], vec![tv("")]]);
+        close(ev("DCOUNTA", vec![rf(db.clone()), t("Index"), rf(all)]), 4.0);
+
+        // Under a label that names no field, "" is a condition that never holds.
+        let db = arr(vec![vec![tv("One"), tv("Two"), tv("Three")], vec![tv("a"), tv("c"), tv("x")], vec![tv("b"), tv("d"), tv("y")]]);
+        let get = |label: Value, value: Value| {
+            let crit = arr(vec![vec![tv("One"), label, tv("Three")], vec![tv("a"), value, tv("x")]]);
+            ev("DGET", vec![rf(db.clone()), t("One"), rf(crit)])
+        };
+        is_text(get(Value::Empty, Value::Empty), "a");
+        is_text(get(tv(""), Value::Empty), "a");
+        is_err(get(Value::Empty, tv("")), CellError::Value);
+        is_err(get(tv(""), tv("")), CellError::Value);
+    }
+
+    /// Expected results are Excel's, from Apache POI's `DGet.xls` (rows 108-119).
+    #[test]
+    fn dget_skips_empty_fields() {
+        let db = arr(vec![
+            vec![tv("One"), tv("Two")],
+            vec![tv("a"), Value::Empty],
+            vec![tv("b"), tv(" ")],
+            vec![tv("c"), tv("")],
+            vec![tv("d"), Value::Error(CellError::NA)],
+            vec![tv("j"), Value::Empty],
+            vec![tv("j"), tv("Text")],
+            vec![tv("j"), Value::Empty],
+            vec![tv("k"), Value::Empty],
+            vec![tv("k"), tv("")],
+        ]);
+        let get = |one: &str| {
+            let crit = arr(vec![vec![tv("One")], vec![tv(one)]]);
+            ev("DGET", vec![rf(db.clone()), t("Two"), rf(crit)])
+        };
+        is_err(get("a"), CellError::Value);
+        is_text(get("b"), " ");
+        is_err(get("c"), CellError::Value);
+        is_err(get("d"), CellError::NA);
+        is_text(get("j"), "Text");
+        is_err(get("k"), CellError::Value);
+    }
 }
diff --git a/crates/functions/src/date.rs b/crates/functions/src/date.rs
index 29aeb47..f68f26d 100644
--- a/crates/functions/src/date.rs
+++ b/crates/functions/src/date.rs
@@ -1,6 +1,6 @@
 //! Date and time functions.
 
-use gridcraft_core::date::{DateTime, datetime_from_serial, days_in_month, days_in_month_in, is_leap, serial_from_ymd};
+use gridcraft_core::date::{DateTime, datetime_from_serial, days_in_month, days_in_month_in, is_leap, serial_from_ymd, serial_in_system};
 use gridcraft_core::parse::parse_input;
 use gridcraft_core::{CellError, DateSystem, Value};
 
@@ -98,10 +98,10 @@ fn second(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
 }
 
 fn now(_a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
-    num_val(c.now_serial())
+    num_val(serial_in_system(c.date_system(), c.now_serial()))
 }
 fn today(_a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
-    num_val(c.now_serial().floor())
+    num_val(serial_in_system(c.date_system(), c.now_serial()).floor())
 }
 
 fn weekday(a: &[Arg], c: &mut dyn Ctx) -> R<Value> {
@@ -794,6 +794,11 @@ mod tests {
         close(crate::call(spec, &[n(0.0)], &mut ctx), 6.0);
         let spec = crate::lookup("YEAR").unwrap();
         close(crate::call(spec, &[n(0.0)], &mut ctx), 1904.0);
+        // The clock is 2026-10-07 12:00; in the 1904 system that is serial 44840.5.
+        close(crate::call(crate::lookup("NOW").unwrap(), &[], &mut ctx), 44840.5);
+        let today = crate::call(crate::lookup("TODAY").unwrap(), &[], &mut ctx);
+        close(today.clone(), 44840.0);
+        close(crate::call(spec, &[crate::Arg::val(today)], &mut ctx), 2026.0);
         // No fictitious day here: 1904 is a real leap year and 1900 is before the epoch.
         let spec = crate::lookup("DATE").unwrap();
         close(crate::call(spec, &[n(1904.0), n(2.0), n(29.0)], &mut ctx), 59.0);
diff --git a/crates/functions/src/dynamic.rs b/crates/functions/src/dynamic.rs
index 3a66ca8..2e29b41 100644
--- a/crates/functions/src/dynamic.rs
+++ b/crates/functions/src/dynamic.rs
@@ -30,6 +30,11 @@ fn rows_of(a: &Array) -> Vec<Vec<Value>> {
     (0..a.rows).map(|r| (0..a.cols).map(|c| a.get(r, c).cloned().unwrap_or(Value::Empty)).collect()).collect()
 }
 
+/// `#NUM!` when an `h` x `w` output would exceed the function cell budget.
+fn check_output_size(h: usize, w: usize) -> R<()> {
+    if h.saturating_mul(w) > MAX_CELLS { Err(CellError::Num) } else { Ok(()) }
+}
+
 /// Builds an array from rows (all rows padded to the widest with `pad`). Empty → `#CALC!`.
 fn from_rows(rows: Vec<Vec<Value>>, pad: &Value) -> R<Value> {
     let h = rows.len();
@@ -37,9 +42,7 @@ fn from_rows(rows: Vec<Vec<Value>>, pad: &Value) -> R<Value> {
     if h == 0 || w == 0 {
         return Err(CellError::Calc);
     }
-    if h.saturating_mul(w) > MAX_CELLS {
-        return Err(CellError::Num);
-    }
+    check_output_size(h, w)?;
     let mut data = Vec::with_capacity(h * w);
     for mut r in rows {
         r.resize(w, pad.clone());
@@ -321,16 +324,20 @@ fn vstack(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
 fn hstack(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     let mut arrays = Vec::new();
     let mut h = 0usize;
+    let mut w = 0usize;
     let mut total = 0usize;
     for i in 0..args.len() {
         let a = arr_arg(args, i)?;
         h = h.max(a.rows);
+        w = w.saturating_add(a.cols);
         total = total.saturating_add(a.data.len());
         if total > MAX_CELLS {
             return Err(CellError::Num);
         }
         arrays.push(a);
     }
+    // The padded rectangle can be far larger than the inputs; refuse it before building any rows.
+    check_output_size(h, w)?;
     let mut rows = vec![Vec::new(); h];
     for a in &arrays {
         for (r, row) in rows.iter_mut().enumerate() {
@@ -785,6 +792,12 @@ fn groupby(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     from_rows(out, &Value::Empty)
 }
 
+/// Height and width of a PIVOTBY grid: `header_rows` (one per column field, plus the value-name row) and
+/// `body_rows` (row keys plus the total row), each `lead` row-field cells wide plus `value_cols` cells per column key.
+fn pivot_dims(header_rows: usize, body_rows: usize, col_keys: usize, value_cols: usize, lead: usize) -> (usize, usize) {
+    (header_rows.saturating_add(body_rows), col_keys.saturating_mul(value_cols).saturating_add(lead))
+}
+
 fn pivotby(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     let rf = arr_arg(args, 0)?;
     let cf = arr_arg(args, 1)?;
@@ -801,9 +814,6 @@ fn pivotby(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     let ckeys: Vec<Vec<Value>> = p.rows.iter().map(|&r| key_row(&cf, r)).collect();
     let rk = distinct_keys(&rkeys, if row_sort.unsigned_abs() as usize <= rf.cols { row_sort } else { 0 });
     let ck = distinct_keys(&ckeys, if col_sort.unsigned_abs() as usize <= cf.cols { col_sort } else { 0 });
-    if rk.len().saturating_add(2).saturating_mul((ck.len() + 1).saturating_mul(vals.cols).saturating_add(rf.cols)) > MAX_CELLS {
-        return Err(CellError::Num);
-    }
     let mut cell: HashMap<(String, String), Vec<usize>> = HashMap::new();
     for ((r, c), &i) in rkeys.iter().zip(ckeys.iter()).zip(p.rows.iter()) {
         cell.entry((row_key(r), row_key(c))).or_default().push(i);
@@ -832,6 +842,14 @@ fn pivotby(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
         cols.insert(0, None);
     }
     let lead = rf.cols;
+    let value_row = vals.cols > 1 || p.show_headers;
+    let header_rows = cf.cols.saturating_add(usize::from(value_row));
+    let body_rows = rk.len().saturating_add(usize::from(row_total != 0));
+    // Reject before building any header or body row: every column-field header row is as wide as the whole grid.
+    let (height, width) = pivot_dims(header_rows, body_rows, cols.len(), vals.cols, lead);
+    if height.saturating_mul(width) > MAX_CELLS {
+        return Err(CellError::Num);
+    }
     let mut out: Vec<Vec<Value>> = Vec::new();
     // Column header rows: one per column field, plus value names when several value columns.
     for level in 0..cf.cols {
@@ -847,7 +865,7 @@ fn pivotby(args: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
         }
         out.push(line);
     }
-    if vals.cols > 1 || p.show_headers {
+    if value_row {
         let mut line: Vec<Value> = if p.show_headers { p.field_headers.iter().take(lead).cloned().collect() } else { vec![Value::Empty; lead] };
         line.resize(lead, Value::Empty);
         for _ in &cols {
@@ -1132,6 +1150,17 @@ mod tests {
         is_err(ev("TOROW", vec![av(arr(vec![vec![Value::Empty]])), n(1.0)]), CellError::Calc);
     }
 
+    #[test]
+    fn output_size_checked_before_padding() {
+        assert_eq!(super::check_output_size(1_000_001, 10), Err(CellError::Num));
+        assert_eq!(super::check_output_size(usize::MAX, 2), Err(CellError::Num));
+        assert_eq!(super::check_output_size(1_000_000, 10), Ok(()));
+        // A 1M-row column beside a 9-wide row: ~1M input cells, but the padded result would be 10,000,010.
+        let tall = Value::from(gridcraft_core::Array::column(vec![nv(1.0); 1_000_001]));
+        let wide = row(&[1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0]);
+        is_err(ev("HSTACK", vec![av(tall), av(wide)]), CellError::Num);
+    }
+
     #[test]
     fn wrapping() {
         let r = ev("WRAPROWS", vec![av(row(&[1.0, 2.0, 3.0, 4.0, 5.0])), n(2.0)]);
@@ -1225,4 +1254,29 @@ mod tests {
             ]
         );
     }
+
+    #[test]
+    fn pivotby_size_check_counts_column_header_rows() {
+        // One row, n column fields and n value columns: n header rows + value-name row + body row + total row,
+        // each 1 + 2n wide. The size checked up front matches the grid PIVOTBY builds.
+        let dims = |k: u32, totals: bool| {
+            let fields: Vec<f64> = (0..k).map(f64::from).collect();
+            let mut args = vec![av(row(&[1.0])), av(row(&fields)), av(row(&fields)), t("SUM")];
+            if !totals {
+                args.extend([empty(), n(0.0), empty(), n(0.0)]);
+            }
+            let r = rows_of(&ev("PIVOTBY", args));
+            (r.len(), r.first().map_or(0, Vec::len))
+        };
+        assert_eq!(dims(2, true), super::pivot_dims(3, 2, 2, 2, 1));
+        assert_eq!(dims(10, true), (13, 21));
+        assert_eq!(dims(10, true), super::pivot_dims(11, 2, 2, 10, 1));
+        assert_eq!(dims(10, false), (12, 11));
+        assert_eq!(dims(10, false), super::pivot_dims(11, 1, 1, 10, 1));
+        // n = 2300: the 2300 header rows alone are 10.58M cells, so the check must count them before any is built.
+        let (h, w) = super::pivot_dims(2301, 2, 2, 2300, 1);
+        assert!(2300 * w > crate::util::MAX_CELLS && h * w > crate::util::MAX_CELLS);
+        let wide: Vec<f64> = (0..2300).map(f64::from).collect();
+        is_err(ev("PIVOTBY", vec![av(row(&[1.0])), av(row(&wide)), av(row(&wide)), t("SUM")]), CellError::Num);
+    }
 }
diff --git a/crates/functions/src/lib.rs b/crates/functions/src/lib.rs
index 282b230..148d682 100644
--- a/crates/functions/src/lib.rs
+++ b/crates/functions/src/lib.rs
@@ -15,7 +15,7 @@
 use std::collections::HashMap;
 use std::sync::OnceLock;
 
-use gridcraft_core::{CellError, DateSystem, Value};
+use gridcraft_core::{Array, CellError, DateSystem, Value};
 
 /// Builds a [`FnSpec`] whose implementation returns `Result<Value, CellError>`.
 ///
@@ -105,6 +105,12 @@ pub trait Ctx {
     fn now_serial(&self) -> f64;
     /// Uniform in [0, 1).
     fn random(&mut self) -> f64;
+    /// For the database functions: whether the formula in the criteria cell at (`row`, `col`) holds
+    /// for `record` (a row of `db` below its labels). `None` when that cell holds no formula or the
+    /// criteria didn't come from a reference.
+    fn computed_criterion(&mut self, _row: usize, _col: usize, _db: &Array, _record: usize) -> Option<bool> {
+        None
+    }
 }
 
 pub type FnImpl = fn(&[Arg], &mut dyn Ctx) -> Value;
@@ -197,7 +203,8 @@ fn registry() -> &'static (Vec<FnSpec>, HashMap<&'static str, usize>) {
     })
 }
 
-/// Looks a function up by name (case-insensitive; `_xlfn.`, `_xlws.` and `_xludf.`-free names).
+/// Looks a function up by name (case-insensitive; `_xlfn.`- and `_xlws.`-free names). A
+/// `_xludf.` name is user-defined and never found.
 pub fn lookup(name: &str) -> Option<&'static FnSpec> {
     let mut n = name.trim().to_ascii_uppercase();
     loop {
diff --git a/crates/functions/src/math.rs b/crates/functions/src/math.rs
index bab219e..7611dc4 100644
--- a/crates/functions/src/math.rs
+++ b/crates/functions/src/math.rs
@@ -75,7 +75,15 @@ fn round_dir(x: f64, digits: i32, up: bool) -> f64 {
     }
     let s = clean(scaled);
     let r = if up { s.ceil() } else { s.floor() };
-    let out = if neg { r * f } else { clean(r / f) };
+    // Toward zero, r == 0 with an infinite scale would be 0 * inf = NaN (#NUM!); the result is simply
+    // zero. Away from zero the true result (10^309 or more) is not a number, so ROUNDUP stays #NUM!.
+    let out = if !neg {
+        clean(r / f)
+    } else if r == 0.0 && !up {
+        0.0
+    } else {
+        r * f
+    };
     if x < 0.0 { -out } else { out }
 }
 
@@ -634,16 +642,18 @@ fn radians(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
 
 const NUMERALS: [(char, u32); 7] = [('I', 1), ('V', 5), ('X', 10), ('L', 50), ('C', 100), ('D', 500), ('M', 1000)];
 
-/// Tokens (text, value) for a ROMAN form, largest value first. Form 0 is classic; higher forms
-/// allow subtracting progressively smaller numerals (max ratio 10, 20, 50, 100, 1000).
+/// Tokens (text, value) for a ROMAN form, largest value first. Form 0 is classic; each higher
+/// form widens one of two limits on the subtracted numeral's ratio to the larger one, alternating:
+/// the limit for I/X/C (10, 10, 100, 100, 1000) and for V/L (none, 20, 20, 200, 200). So form 2
+/// allows IC and XM but not VD, and form 3 adds VD and VM but not ID.
 fn roman_tokens(form: u32) -> Vec<(String, u32)> {
-    let max_ratio = [10, 20, 50, 100, 1000].get(form as usize).copied().unwrap_or(10);
+    let (pow10_max, five_max) = [(10, 0), (10, 20), (100, 20), (100, 200), (1000, 200)].get(form as usize).copied().unwrap_or((10, 0));
     let mut toks: Vec<(String, u32)> = NUMERALS.iter().map(|(c, v)| (c.to_string(), *v)).collect();
     for (i, (sc, sv)) in NUMERALS.iter().enumerate() {
         for (lc, lv) in NUMERALS.iter().skip(i + 1) {
             let ratio = lv / sv;
             let pow10 = matches!(sc, 'I' | 'X' | 'C');
-            let ok = if form == 0 { pow10 && ratio <= 10 } else { ratio <= max_ratio };
+            let ok = ratio <= if pow10 { pow10_max } else { five_max };
             let value = lv - sv;
             // Skip pairs that equal a single numeral (VX = V) – they are never shorter.
             if ok && !NUMERALS.iter().any(|(_, v)| *v == value) {
@@ -950,6 +960,9 @@ fn criteria_mask(a: &[Arg], first_pair: usize, rows: usize, cols: usize) -> R<Ve
     if rest.is_empty() || rest.len() % 2 != 0 {
         return Err(CellError::Value);
     }
+    // A text criterion over 255 characters is `#VALUE!` only when there is a single criteria
+    // pair. With two or more pairs Excel matches its first 255 characters instead.
+    let single_pair = rest.len() == 2;
     let mut mask = vec![true; rows.saturating_mul(cols)];
     for pair in rest.chunks(2) {
         let (Some(range), Some(crit)) = (pair.first(), pair.get(1)) else { return Err(CellError::Value) };
@@ -957,7 +970,8 @@ fn criteria_mask(a: &[Arg], first_pair: usize, rows: usize, cols: usize) -> R<Ve
         if r.rows != rows || r.cols != cols {
             return Err(CellError::Value);
         }
-        let c = Criterion::parse(&crit.value.scalar());
+        let scalar = crit.value.scalar();
+        let c = if single_pair { Criterion::parse_arg(&scalar)? } else { Criterion::parse_arg_truncated(&scalar) };
         for (m, v) in mask.iter_mut().zip(r.iter()) {
             if *m && !c.matches(v) {
                 *m = false;
@@ -1017,7 +1031,7 @@ fn minifs(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
 
 fn countif(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     let range = as_array(&crate::util::arg(a, 0)?.value);
-    let c = Criterion::parse(&crate::util::arg(a, 1)?.value.scalar());
+    let c = Criterion::parse_arg(&crate::util::arg(a, 1)?.value.scalar())?;
     num_val(range.iter().filter(|v| c.matches(v)).count() as f64)
 }
 
@@ -1026,7 +1040,7 @@ fn countif(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
 /// the evaluator does that resizing (it has the references), so cells line up one to one here.
 fn if_numbers(a: &[Arg]) -> R<Vec<f64>> {
     let range = as_array(&crate::util::arg(a, 0)?.value);
-    let c = Criterion::parse(&crate::util::arg(a, 1)?.value.scalar());
+    let c = Criterion::parse_arg(&crate::util::arg(a, 1)?.value.scalar())?;
     let sum_range = if has(a, 2) { Some(as_array(&crate::util::arg(a, 2)?.value)) } else { None };
     let mut out = Vec::new();
     for r in 0..range.rows {
@@ -1373,6 +1387,13 @@ mod tests {
         close(ev2("ROUNDDOWN", -3.9, 0.0), -3.0);
         close(ev2("ROUNDDOWN", 2.71989, 3.0), 2.719);
         close(ev2("ROUNDDOWN", 31415.92654, -2.0), 31400.0);
+        for digits in [-308.0, -309.0, -400.0] {
+            for x in [1234.0, -1234.0, 0.5] {
+                close(ev2("ROUNDDOWN", x, digits), 0.0);
+                close(ev2("TRUNC", x, digits), 0.0);
+            }
+        }
+        assert!(matches!(ev2("ROUNDUP", 1234.0, -309.0), Value::Error(CellError::Num)));
         close(ev2("ROUNDUP", 0.1 + 0.2, 1.0), 0.3);
         close(ev2("TRUNC", 8.987, 2.0), 8.98);
         close(ev1("TRUNC", -8.9), -8.0);
@@ -1553,6 +1574,43 @@ mod tests {
         is_err(ev("DECIMAL", vec![t("12"), n(2.0)]), Num);
     }
 
+    /// Every number where Excel's forms 2 and 3 differ from a plain ratio limit (issue #733):
+    /// form 2 subtracts I from C and X from M, form 3 also V from M.
+    #[test]
+    fn roman_forms_two_and_three_match_excel() {
+        const HUNDREDS: [&str; 10] = ["", "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"];
+        const ONES: [&str; 10] = ["", "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"];
+        let mut cases = Vec::new();
+        for thousands in 0..4usize {
+            let m = "M".repeat(thousands);
+            for (h, hundreds) in HUNDREDS.iter().enumerate() {
+                if h != 4 && h != 9 {
+                    cases.push((thousands * 1000 + h * 100 + 99, 2.0, format!("{m}{hundreds}IC")));
+                }
+            }
+            for (o, ones) in ONES.iter().enumerate() {
+                cases.push((thousands * 1000 + 990 + o, 2.0, format!("{m}XM{ones}")));
+            }
+            for (o, ones) in ONES.iter().enumerate().take(5) {
+                cases.push((thousands * 1000 + 995 + o, 3.0, format!("{m}VM{ones}")));
+            }
+        }
+        assert_eq!(cases.len(), 92);
+        for (number, form, want) in &cases {
+            is_text(ev2("ROMAN", *number as f64, *form), want);
+        }
+        // Neighbours that already matched: form 2 still has no VD or ID, form 3 no ID.
+        is_text(ev2("ROMAN", 495.0, 2.0), "XDV");
+        is_text(ev2("ROMAN", 495.0, 3.0), "VD");
+        is_text(ev2("ROMAN", 1499.0, 2.0), "MXDIX");
+        is_text(ev2("ROMAN", 999.0, 0.0), "CMXCIX");
+        is_text(ev2("ROMAN", 999.0, 1.0), "LMVLIV");
+        is_text(ev2("ROMAN", 999.0, 4.0), "IM");
+        is_text(ev2("ROMAN", 995.0, 4.0), "VM");
+        is_text(ev2("ROMAN", 99.0, 1.0), "VCIV");
+        is_text(ev2("ROMAN", 99.0, 4.0), "IC");
+    }
+
     #[test]
     fn matrices() {
         let a = arr(vec![vec![nv(1.0), nv(2.0)], vec![nv(3.0), nv(4.0)]]);
@@ -1643,4 +1701,77 @@ mod tests {
         is_err(ev("COUNTIFS", vec![rf(qty.clone()), t(">1"), rf(qty)]), CellError::Value);
         is_err(ev("SUMIF", vec![rf(col(&[1.0, 2.0])), t(">0"), rf(arr(vec![vec![Value::Error(NA)], vec![nv(1.0)]]))]), NA);
     }
+
+    #[test]
+    fn criteria_over_255_chars_are_value_errors_with_one_pair_and_truncated_with_more() {
+        let ok = "x".repeat(255);
+        let long = "x".repeat(256);
+        let cells = arr(vec![vec![tv(&ok)], vec![tv(&long)]]);
+        let qty = col(&[1.0, 2.0]);
+        close(ev("COUNTIF", vec![rf(cells.clone()), t(&ok)]), 1.0);
+        is_err(ev("COUNTIF", vec![rf(cells.clone()), t(&long)]), CellError::Value);
+        close(ev("SUMIFS", vec![rf(qty.clone()), rf(cells.clone()), t(&ok)]), 1.0);
+        is_err(ev("SUMIFS", vec![rf(qty.clone()), rf(cells.clone()), t(&long)]), CellError::Value);
+        is_err(ev("COUNTIFS", vec![rf(cells.clone()), t(&long)]), CellError::Value);
+        // With two or more pairs Excel matches the first 255 characters: the 255-character cell
+        // (quantity 1), not the 256-character one (quantity 2). Checked on Excel 2016 and 365.
+        let over = format!("{ok}y");
+        close(ev("COUNTIFS", vec![rf(cells.clone()), t(&long), rf(qty.clone()), t(">0")]), 1.0);
+        close(ev("SUMIFS", vec![rf(qty.clone()), rf(cells.clone()), t(&long), rf(qty.clone()), t(">0")]), 1.0);
+        close(ev("SUMIFS", vec![rf(qty.clone()), rf(qty.clone()), t(">0"), rf(cells.clone()), t(&over)]), 1.0);
+        close(ev("AVERAGEIFS", vec![rf(qty.clone()), rf(cells.clone()), t(&long), rf(qty.clone()), t(">0")]), 1.0);
+        close(ev("MAXIFS", vec![rf(qty.clone()), rf(cells.clone()), t(&"x".repeat(300)), rf(qty), t(">0")]), 1.0);
+    }
+
+    #[test]
+    fn criteria_over_255_utf16_units_follow_excel() {
+        // The tester's sheet, identical on Excel 2016 and Microsoft 365: A1:A6 hold these
+        // strings, B is the row number, and each row uses its own string as the criterion.
+        let e = "😀";
+        let strings =
+            [e.repeat(127), e.repeat(128), format!("{}{e}", "a".repeat(254)), format!("{}{e}", "a".repeat(253)), e.repeat(200), "я".repeat(256)];
+        let cells = arr(strings.iter().map(|s| vec![tv(s)]).collect());
+        let rows = col(&[1.0, 2.0, 3.0, 4.0, 5.0, 6.0]);
+        // COUNTIF, SUMIF, COUNTIFS with one pair, SUMIFS with a second pair `B,">0"`.
+        let expected: [Option<[f64; 4]>; 6] = [Some([1.0, 1.0, 1.0, 1.0]), None, None, Some([1.0, 4.0, 1.0, 4.0]), None, None];
+        for (s, want) in strings.iter().zip(expected) {
+            let countif = ev("COUNTIF", vec![rf(cells.clone()), t(s)]);
+            let sumif = ev("SUMIF", vec![rf(cells.clone()), t(s), rf(rows.clone())]);
+            let countifs = ev("COUNTIFS", vec![rf(cells.clone()), t(s)]);
+            let sumifs = ev("SUMIFS", vec![rf(rows.clone()), rf(cells.clone()), t(s), rf(rows.clone()), t(">0")]);
+            match want {
+                Some([a, b, c, d]) => {
+                    close(countif, a);
+                    close(sumif, b);
+                    close(countifs, c);
+                    close(sumifs, d);
+                }
+                // Over 255 units: `#VALUE!` with one pair; cut to 255 units with two, which
+                // matches no cell (for emoji it splits a surrogate pair).
+                None => {
+                    is_err(countif, CellError::Value);
+                    is_err(sumif, CellError::Value);
+                    is_err(countifs, CellError::Value);
+                    close(sumifs, 0.0);
+                }
+            }
+        }
+    }
+
+    #[test]
+    fn criteria_cut_inside_a_surrogate_pair() {
+        let e = "😀";
+        let cells = arr(vec![vec![tv(&e.repeat(127))], vec![tv(&e.repeat(128))], vec![tv("zzz")], vec![Value::Empty]]);
+        let rows = col(&[1.0, 2.0, 3.0, 4.0]);
+        let sumifs = |crit: String| ev("SUMIFS", vec![rf(rows.clone()), rf(cells.clone()), t(&crit), rf(rows.clone()), t(">0")]);
+        // "=" + 😀×128 is 257 units: the cut after 255 keeps "=" and 127 whole emoji.
+        close(sumifs(format!("={}", e.repeat(128))), 1.0);
+        // With a two-unit prefix the cut keeps 126 emoji and half of the 127th. Such a criterion
+        // equals no cell text: "=" matches nothing and "<>" everything, blanks included.
+        close(sumifs(format!("=a{}", e.repeat(128))), 0.0);
+        close(sumifs(format!("<>{}", e.repeat(128))), 10.0);
+        // Comparisons treat it as sorting just above the 126 kept emoji.
+        close(sumifs(format!(">={}", e.repeat(128))), 1.0 + 2.0);
+        close(sumifs(format!("<={}", e.repeat(128))), 3.0);
+    }
 }
diff --git a/crates/functions/src/stat.rs b/crates/functions/src/stat.rs
index 25449bd..7c50abe 100644
--- a/crates/functions/src/stat.rs
+++ b/crates/functions/src/stat.rs
@@ -79,10 +79,12 @@ fn mode_sngl(v: &[f64]) -> R<f64> {
 }
 
 /// Numbers for MODE / MODE.SNGL / MODE.MULT. Inside multi-cell ranges and arrays only numbers
-/// count, like [`numbers`]. Scalar arguments are stricter than in SUM: Excel answers `#VALUE!`
-/// for direct text (even numeric text such as `"1"`) and for a single-cell reference to text or
-/// a blank cell (observed: `MODE(B8,"1",2,3)` and `MODE(B9,2,D7)` with D7 blank are `#VALUE!`).
-/// Arguments are processed left to right, so the first error wins.
+/// count, like [`numbers`]. Scalar arguments differ from SUM: in Excel 365, text and logical
+/// values are skipped whether typed or referenced (even numeric text such as `"1"`, so
+/// `MODE(1,"1",2,3)` is `#N/A`, and `MODE(1,TRUE,TRUE,2)` is `#N/A`), but a single-cell reference
+/// to a blank cell is `#VALUE!` (`MODE(B9,2,D7)` with D7 blank). Arguments are processed left to
+/// right, so the first error wins. The results cached in POI's FormulaEvalTestData come from an
+/// older Excel that answered `#VALUE!` for typed text; they are not the reference here.
 fn mode_numbers(args: &[Arg]) -> R<Vec<f64>> {
     let mut out = Vec::new();
     for a in args {
@@ -98,9 +100,8 @@ fn mode_numbers(args: &[Arg]) -> R<Vec<f64>> {
             }
             Value::Number(n) => out.push(*n),
             Value::Error(e) => return Err(*e),
-            Value::Text(_) | Value::Empty => return Err(CellError::Value),
-            Value::Bool(_) if a.from_ref => {}
-            v => out.push(v.to_number()?),
+            Value::Text(_) | Value::Bool(_) => {}
+            Value::Empty => return Err(CellError::Value),
         }
     }
     Ok(out)
@@ -461,7 +462,7 @@ fn prob(a: &[Arg], _: C) -> R<Value> {
     let (xs, ps) = arg_pairs(a, 0, 1)?;
     let lo = num(a, 2)?;
     let hi = if has(a, 3) { num(a, 3)? } else { lo };
-    if ps.iter().any(|&p| !(0.0..=1.0).contains(&p)) {
+    if ps.iter().any(|&p| p <= 0.0 || p > 1.0) {
         return Err(CellError::Num);
     }
     let total: f64 = ps.iter().sum();
@@ -2279,9 +2280,11 @@ mod tests {
         assert_eq!(rows_of(&ev("MODE.MULT", vec![c(&[1.0, 2.0, 3.0, 4.0, 3.0, 2.0, 1.0, 2.0, 3.0])])), vec![vec![nv(2.0)], vec![nv(3.0)]]);
     }
 
-    /// MODE argument semantics observed in Excel (FormulaEvalTestData, row "Mode"): multi-cell
-    /// ranges skip text and blanks, but direct text and single-cell references to text or blank
-    /// cells are `#VALUE!`; the first error from the left wins.
+    /// MODE argument semantics in Excel 365, on the inputs of FormulaEvalTestData (row "Mode"):
+    /// text is skipped, typed or referenced, but a single-cell reference to a blank cell is
+    /// `#VALUE!`; the first error from the left wins. The values cached in POI's file come from an
+    /// older Excel and say `#VALUE!` for `MODE(C9,E16,"1",B8)`, `MODE(B8,"1",2,3)` and
+    /// `MODE("1",1,#DIV/0!,2,3)`; Excel 365 gives `#N/A`, `#N/A` and `#DIV/0!`.
     #[test]
     fn mode_scalar_arguments() {
         let data = arr(vec![vec![tv(""), nv(0.0), nv(1.0)], vec![tv("x"), nv(1.0), nv(1.001)], vec![tv("y"), nv(9e9), nv(2.3456)]]);
@@ -2290,9 +2293,9 @@ mod tests {
             (vec![rf(data)], Ok(1.0)),
             (vec![rf(arr(vec![vec![nv(-1.1), Value::Empty, tv("1.1")]])), n(-1.1)], Ok(-1.1)),
             // MODE(C9,E16,"1",B8): E16 holds the text "1.1".
-            (vec![rf(nv(1.1)), rf(tv("1.1")), t("1"), rf(nv(1.0))], Err(CellError::Value)),
-            (vec![rf(nv(1.0)), t("1"), n(2.0), n(3.0)], Err(CellError::Value)),
-            (vec![t("1"), n(1.0), e(CellError::Div0), n(2.0), n(3.0)], Err(CellError::Value)),
+            (vec![rf(nv(1.1)), rf(tv("1.1")), t("1"), rf(nv(1.0))], Err(CellError::NA)),
+            (vec![rf(nv(1.0)), t("1"), n(2.0), n(3.0)], Err(CellError::NA)),
+            (vec![t("1"), n(1.0), e(CellError::Div0), n(2.0), n(3.0)], Err(CellError::Div0)),
             // MODE(B9,2,D7) with D7 blank.
             (vec![rf(nv(2.0)), n(2.0), rf(Value::Empty)], Err(CellError::Value)),
             (vec![n(1.0), n(1.0), e(CellError::Div0), t("1")], Err(CellError::Div0)),
@@ -2305,7 +2308,31 @@ mod tests {
                 }
             }
         }
-        is_err(ev("MODE.MULT", vec![rf(nv(1.0)), t("1"), n(1.0)]), CellError::Value);
+        is_err(ev("MODE.MULT", vec![rf(nv(1.0)), t("1"), rf(Value::Empty)]), CellError::Value);
+    }
+
+    /// Text and logical values typed as arguments are skipped, not coerced (Excel 365, #736).
+    #[test]
+    fn mode_skips_typed_text_and_logicals() {
+        let cases: Vec<(Vec<crate::Arg>, Result<f64, CellError>)> = vec![
+            (vec![n(1.0), n(1.0), t("x")], Ok(1.0)),
+            (vec![n(1.0), n(2.0), t("x")], Err(CellError::NA)),
+            (vec![n(1.0), t("1"), n(2.0), n(3.0)], Err(CellError::NA)),
+            (vec![t("1"), n(1.0), n(2.0), n(3.0)], Err(CellError::NA)),
+            (vec![t("1"), n(1.0), e(CellError::Div0), n(2.0), n(3.0)], Err(CellError::Div0)),
+            (vec![n(1.0), b(true), b(true), n(2.0)], Err(CellError::NA)),
+            (vec![n(1.0), n(1.0), b(true)], Ok(1.0)),
+        ];
+        for name in ["MODE", "MODE.SNGL"] {
+            for (args, want) in &cases {
+                match want {
+                    Ok(x) => close(ev(name, args.clone()), *x),
+                    Err(err) => is_err(ev(name, args.clone()), *err),
+                }
+            }
+        }
+        assert_eq!(rows_of(&ev("MODE.MULT", vec![n(1.0), t("1"), n(1.0), t("x")])), vec![vec![nv(1.0)]]);
+        is_err(ev("MODE.MULT", vec![n(1.0), b(true), b(true), n(2.0)]), CellError::NA);
     }
 
     #[test]
@@ -2472,7 +2499,10 @@ mod tests {
         let p = c(&[0.2, 0.3, 0.1, 0.4]);
         close(ev("PROB", vec![x.clone(), p.clone(), n(2.0)]), 0.1);
         close(ev("PROB", vec![x.clone(), p, n(1.0), n(3.0)]), 0.8);
-        is_err(ev("PROB", vec![x, c(&[0.5, 0.5, 0.5, 0.5]), n(1.0)]), CellError::Num);
+        is_err(ev("PROB", vec![x.clone(), c(&[0.5, 0.5, 0.5, 0.5]), n(1.0)]), CellError::Num);
+        // Excel: any probability <= 0 is #NUM!, even when it sums to one and lies outside the limits.
+        is_err(ev("PROB", vec![x.clone(), c(&[0.5, 0.0, 0.25, 0.25]), n(0.0), n(3.0)]), CellError::Num);
+        is_err(ev("PROB", vec![x, c(&[0.5, 0.0, 0.25, 0.25]), n(2.0), n(3.0)]), CellError::Num);
     }
 
     #[test]
diff --git a/crates/functions/src/text.rs b/crates/functions/src/text.rs
index 723cd4a..6270866 100644
--- a/crates/functions/src/text.rs
+++ b/crates/functions/src/text.rs
@@ -5,7 +5,8 @@ use gridcraft_core::{CellError, Value, number_to_text};
 
 use crate::criteria::wildcard_find;
 use crate::util::{
-    A, MAX_TEXT, R, S, arg, array_val, as_array, boolean, has, num, num_val, opt_bool, opt_int, opt_num, round_half_away, scalar, text, text_val,
+    A, MAX_CELLS, MAX_TEXT, R, S, arg, array_val, as_array, boolean, has, num, num_val, opt_bool, opt_int, opt_num, round_half_away, scalar, text,
+    text_val,
 };
 use crate::{Arg, Ctx, FnSpec, VAR};
 
@@ -214,7 +215,7 @@ fn find_impl(a: &[Arg], wild: bool) -> R<Value> {
     let hay = text(a, 1)?;
     let start = opt_num(a, 2, 1.0)?;
     let hc = chars(&hay);
-    if (start.is_nan() || start < 1.0) || start > hc.len() as f64 + 1.0 {
+    if (start.is_nan() || start < 1.0) || start > hc.len().max(1) as f64 {
         return Err(CellError::Value);
     }
     let start = start as usize - 1;
@@ -610,6 +611,9 @@ fn textsplit(a: &[Arg], _c: &mut dyn Ctx) -> R<Value> {
     }
     let ncols = rows.iter().map(Vec::len).max().unwrap_or(1).max(1);
     let nrows = rows.len();
+    if nrows.saturating_mul(ncols) > MAX_CELLS {
+        return Err(CellError::Num);
+    }
     let mut data = Vec::with_capacity(nrows * ncols);
     for r in rows {
         let n = r.len();
@@ -1032,6 +1036,10 @@ mod tests {
         close(ev("SEARCH", vec![t("~*"), t("a*b")]), 2.0);
         is_err(ev("SEARCH", vec![t("z"), t("abc")]), CellError::Value);
         is_err(ev("SEARCH", vec![t("a"), t("abc"), n(5.0)]), CellError::Value);
+        for f in ["FIND", "SEARCH"] {
+            close(ev(f, vec![t(""), t("abc"), n(3.0)]), 3.0);
+            is_err(ev(f, vec![t(""), t("abc"), n(4.0)]), CellError::Value);
+        }
         assert_eq!(ev("EXACT", vec![t("a"), t("A")]), Value::Bool(false));
         assert_eq!(ev("EXACT", vec![t("a"), t("a")]), Value::Bool(true));
     }
@@ -1133,6 +1141,13 @@ mod tests {
         assert_eq!(rows_of(&v)[1], vec![tv("c"), tv("-")]);
     }
 
+    #[test]
+    fn split_rejects_oversized_padded_grid() {
+        // One row of 8000 columns followed by 8000 one-cell rows: the text is under the cell-text limit, the padded grid is not.
+        let text = format!("{}{}", "a,".repeat(8000), "b;".repeat(8000));
+        is_err(ev("TEXTSPLIT", vec![t(&text), t(","), t(";")]), CellError::Num);
+    }
+
     #[test]
     fn to_text() {
         is_text(ev("VALUETOTEXT", vec![t("a\"b")]), "a\"b");
diff --git a/crates/mcp/src/tests.rs b/crates/mcp/src/tests.rs
index eb1f205..de6bbc6 100644
--- a/crates/mcp/src/tests.rs
+++ b/crates/mcp/src/tests.rs
@@ -202,6 +202,9 @@ fn basic_tools() {
     assert!(f.as_array().unwrap().iter().any(|x| x["name"] == "VLOOKUP"));
     assert_eq!(ok(&mut s, "evaluate_formula", json!({"formula": "SUM(1,2,3)"}))["result"], json!(6.0));
     ok(&mut s, "set_cell", json!({"cell": "A1", "input": "5"}));
+    // #697: a number for `input` is entered, not rejected or cleared.
+    ok(&mut s, "set_cell", json!({"cell": "B1", "input": 42.5}));
+    assert_eq!(ok(&mut s, "get_cell", json!({"cell": "B1"}))["value"], json!(42.5));
     ok(&mut s, "execute_command", json!({"command": "cell.set", "params": {"cell": "A2", "input": "=A1*2"}}));
     assert_eq!(ok(&mut s, "get_cell", json!({"cell": "A2"}))["value"], json!(10.0));
     assert_eq!(ok(&mut s, "evaluate_formula", json!({"formula": "=A1+A2", "cell": "C1"}))["result"], json!(15.0));
@@ -517,3 +520,29 @@ fn text_to_columns_destination_follows_its_sheet() {
     cmd_fails(&mut s, "data.textToColumns", json!({"range": "Other!A1", "delimiters": [","], "destination": "D0"}));
     cmd_fails(&mut s, "data.textToColumns", json!({"range": "Other!A1", "delimiters": [","], "destination": "Sheet1!D1"}));
 }
+
+#[test]
+fn invalid_borders_are_invalid_params() {
+    let mut s = server();
+    let bad = |s: &mut Server, id: u64, borders: Value| {
+        let v = rpc(s, id, "tools/call", json!({"name": "format_range", "arguments": {"range": "A1", "borders": borders}}));
+        assert_eq!(err_code(&v), -32602, "{v}");
+    };
+    bad(&mut s, 1, json!(123));
+    bad(&mut s, 2, json!("bogus"));
+    bad(&mut s, 3, json!({"preset": "bogus"}));
+    bad(&mut s, 4, json!({"style": "thick"}));
+    ok(&mut s, "format_range", json!({"range": "A1", "borders": "all"}));
+    ok(&mut s, "format_range", json!({"range": "B1", "borders": {"preset": "all", "style": "thick", "color": "#123456"}}));
+}
+
+#[test]
+fn invalid_sort_keys_are_invalid_params() {
+    let mut s = server();
+    ok(&mut s, "write_range", json!({"range": "A1", "values": [["b"], ["c"], ["a"]]}));
+    for (id, keys) in [(1, json!([123])), (2, json!([{"order": "desc"}])), (3, json!([{"column": "A", "order": "sideways"}]))] {
+        let v = rpc(&mut s, id, "tools/call", json!({"name": "sort_range", "arguments": {"range": "A1:A3", "keys": keys}}));
+        assert_eq!(err_code(&v), -32602, "{v}");
+    }
+    ok(&mut s, "sort_range", json!({"range": "A1:A3", "keys": ["A", {"column": "A", "order": "desc"}]}));
+}
diff --git a/crates/mcp/src/tools.rs b/crates/mcp/src/tools.rs
index eb741b8..e6322f0 100644
--- a/crates/mcp/src/tools.rs
+++ b/crates/mcp/src/tools.rs
@@ -180,7 +180,7 @@ pub fn tool_definitions() -> Vec<Value> {
             "Enter one cell exactly as if typed: a number, text, or a formula starting with = (\"=AVERAGE(B2:B9)\"). \
              Dependent cells recalculate. Returns the command result; use get_cell to read the computed value.",
             obj(
-                json!({"cell": string("Cell, e.g. \"B7\" or \"Sheet2!C3\""), "input": string("Typed input: number, text or =formula")}),
+                json!({"cell": string("Cell, e.g. \"B7\" or \"Sheet2!C3\""), "input": {"type": ["string", "number", "boolean"], "description": "Typed input: number, text or =formula"}}),
                 &["cell", "input"],
             ),
             false,
@@ -391,8 +391,41 @@ fn type_matches(t: &str, v: &Value) -> bool {
     }
 }
 
-/// Validates `args` against the tool's schema: unknown tool, missing required properties and
-/// top-level type mismatches are JSON-RPC "invalid params" errors.
+/// Checks a value against a (sub)schema: `type`, `enum`, `oneOf`, array `items`, and for objects the required and known properties.
+fn schema_matches(schema: &Value, v: &Value) -> bool {
+    if let Some(t) = schema["type"].as_str()
+        && !type_matches(t, v)
+    {
+        return false;
+    }
+    if let Some(allowed) = schema["enum"].as_array()
+        && !allowed.contains(v)
+    {
+        return false;
+    }
+    if let Some(alts) = schema["oneOf"].as_array()
+        && !alts.iter().any(|alt| schema_matches(alt, v))
+    {
+        return false;
+    }
+    if let Some(xs) = v.as_array()
+        && !xs.iter().all(|x| schema_matches(&schema["items"], x))
+    {
+        return false;
+    }
+    if let Some(o) = v.as_object() {
+        if schema["required"].as_array().into_iter().flatten().filter_map(Value::as_str).any(|r| o.get(r).is_none_or(Value::is_null)) {
+            return false;
+        }
+        if let Some(props) = schema["properties"].as_object() {
+            return o.iter().all(|(k, x)| props.get(k).is_some_and(|ps| x.is_null() || schema_matches(ps, x)));
+        }
+    }
+    true
+}
+
+/// Validates `args` against the tool's schema: unknown tool, missing required properties,
+/// top-level type mismatches and values matching none of a `oneOf` are JSON-RPC "invalid params" errors.
 pub(crate) fn check_arguments(name: &str, args: &Value) -> Result<(), String> {
     let defs = tool_definitions();
     let def = defs.iter().find(|d| d["name"] == name).ok_or_else(|| format!("unknown tool `{name}`"))?;
@@ -421,6 +454,9 @@ pub(crate) fn check_arguments(name: &str, args: &Value) -> Result<(), String> {
         {
             return Err(format!("{name}: `{k}` must be one of {}", Value::Array(allowed.clone())));
         }
+        if (p["oneOf"].is_array() || p["items"]["oneOf"].is_array()) && !schema_matches(p, v) {
+            return Err(format!("{name}: argument `{k}` does not match the schema: {}", p["description"]));
+        }
     }
     Ok(())
 }
diff --git a/crates/model/src/cellmap.rs b/crates/model/src/cellmap.rs
index 0f2c685..dbbe202 100644
--- a/crates/model/src/cellmap.rs
+++ b/crates/model/src/cellmap.rs
@@ -43,7 +43,7 @@ mod tests {
                 dates: vec![],
             },
         );
-        s.hyperlinks.insert(c3, Hyperlink { target: "Sheet1!A1".into(), tooltip: Some("jump".into()) });
+        s.hyperlinks.insert(c3, Hyperlink { target: "Sheet1!A1".into(), tooltip: Some("jump".into()), external: false });
         let json = serde_json::to_string(&s).expect("serialize");
         let back: Sheet = serde_json::from_str(&json).expect("deserialize");
         assert_eq!(back.comments, s.comments);
diff --git a/crates/model/src/features.rs b/crates/model/src/features.rs
index e04db25..7e8e08b 100644
--- a/crates/model/src/features.rs
+++ b/crates/model/src/features.rs
@@ -304,9 +304,14 @@ pub struct Comment {
 
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct Hyperlink {
-    /// URL, `mailto:`, or an in-workbook location like `Sheet2!A1`.
+    /// URL, `mailto:`, a file path (`Book.xlsx`, `Book.xlsx#Sheet1!A2`), or an in-workbook location
+    /// like `Sheet2!A1`.
     pub target: String,
     pub tooltip: Option<String>,
+    /// The target is outside this workbook (Excel's "Existing File or Web Page"): a relationship in
+    /// the file, not a `location`. A bare file name can't be told from a defined name by its text.
+    #[serde(default)]
+    pub external: bool,
 }
 
 // ---------------------------------------------------------------- drawing objects
@@ -975,6 +980,12 @@ pub struct PivotTable {
     pub last_range: Option<RangeRef>,
     /// Calculated fields, usable in the Values area by name.
     pub calculated_fields: Vec<PivotCalcField>,
+    /// The Σ Values pseudo-field (it exists with two or more value fields) sits in Rows rather
+    /// than Columns (Excel's "values on rows").
+    pub values_on_rows: bool,
+    /// Position of Σ Values among the row fields (`None` = after the last). Only used with
+    /// `values_on_rows`: in Columns Σ Values always comes after the last column field.
+    pub values_position: Option<usize>,
 }
 
 /// A calculated field: a formula over other fields (`=Sales*0.1`, `='Unit Price'*Units`). As in
@@ -1007,6 +1018,8 @@ impl Default for PivotTable {
             show_headers: true,
             last_range: None,
             calculated_fields: vec![],
+            values_on_rows: false,
+            values_position: None,
         }
     }
 }
diff --git a/crates/model/src/lib.rs b/crates/model/src/lib.rs
index 1bea842..fa64aad 100644
--- a/crates/model/src/lib.rs
+++ b/crates/model/src/lib.rs
@@ -19,7 +19,7 @@ pub use cell::{Cell, CellPicture, Formula};
 pub use features::*;
 pub use password::PasswordHash;
 pub use preserved::{Preserved, PreservedPart, PreservedRel, PreservedXml};
-pub use sheet::{DEFAULT_COL_WIDTH, DEFAULT_ROW_HEIGHT, LineIndex, Sheet, SheetViewMode, Visibility};
+pub use sheet::{DEFAULT_COL_WIDTH, DEFAULT_ROW_HEIGHT, LineIndex, Sheet, SheetViewMode, Visibility, points_to_chars};
 pub use store::CellStore;
 pub use style::{
     Alignment, BorderLine, BorderStyle, Borders, Color, Fill, Font, HAlign, NumFmt, PatternType, Style, StyleId, StyleTable, Theme, Underline,
diff --git a/crates/model/src/preserved.rs b/crates/model/src/preserved.rs
index 6d0b35d..eb8e2bb 100644
--- a/crates/model/src/preserved.rs
+++ b/crates/model/src/preserved.rs
@@ -33,10 +33,11 @@ pub struct PreservedPart {
 }
 
 /// A raw XML element of an owning part that refers to kept parts, re-emitted on save with its
-/// relationship ids rewritten.
+/// relationship ids rewritten, or that Excel needs back unchanged (the workbook's `fileVersion`).
 #[derive(Clone, Debug, Default, PartialEq, Eq)]
 pub struct PreservedXml {
-    /// Which slot of the owner it belongs in (`externalReferences`, `oleObjects`, `controls`).
+    /// Which slot of the owner it belongs in (`externalReferences`, `fileVersion`, `ext`,
+    /// `oleObjects`, `controls`).
     pub slot: String,
     /// The element, namespace declarations it needs included.
     pub xml: String,
diff --git a/crates/model/src/sheet.rs b/crates/model/src/sheet.rs
index e05d3bf..b404b89 100644
--- a/crates/model/src/sheet.rs
+++ b/crates/model/src/sheet.rs
@@ -117,6 +117,12 @@ pub struct Sheet {
 pub const DEFAULT_COL_WIDTH: f32 = 64.0;
 pub const DEFAULT_ROW_HEIGHT: f32 = 20.0;
 
+/// Column width (points) → characters of the default font's digit width (7 px), without the
+/// cell padding: the value the Column Width dialog shows.
+pub fn points_to_chars(px: f64) -> f64 {
+    if px <= 12.0 { (px / 12.0 * 100.0).round() / 100.0 } else { ((px - 5.0) / 7.0 * 100.0 + 0.5).trunc() / 100.0 }
+}
+
 impl Sheet {
     pub fn new(name: impl Into<String>) -> Sheet {
         Sheet {
diff --git a/crates/model/src/style.rs b/crates/model/src/style.rs
index 126727e..d397687 100644
--- a/crates/model/src/style.rs
+++ b/crates/model/src/style.rs
@@ -377,6 +377,12 @@ impl Default for StyleTable {
 }
 
 impl StyleTable {
+    /// A table whose default (Normal) style is `normal`, such as a file's own Normal font.
+    pub fn with_default(normal: Style) -> Self {
+        let mut index = HashMap::new();
+        index.insert(normal.clone(), StyleId::DEFAULT);
+        StyleTable { styles: vec![normal], index }
+    }
     pub fn get(&self, id: StyleId) -> &Style {
         self.styles.get(id.0 as usize).or_else(|| self.styles.first()).unwrap_or(&DEFAULT_STYLE)
     }
diff --git a/crates/numfmt/src/lib.rs b/crates/numfmt/src/lib.rs
index 674e844..e5c65bd 100644
--- a/crates/numfmt/src/lib.rs
+++ b/crates/numfmt/src/lib.rs
@@ -101,6 +101,8 @@ impl Default for NumberFormat {
 impl NumberFormat {
     /// Parses a format code. Never fails: unknown or malformed parts degrade to literal text.
     pub fn parse(code: &str) -> NumberFormat {
+        #[cfg(test)]
+        parse_cache::count_parse();
         let trimmed = code.trim();
         // `checkbox` marks a checkbox cell (Insert › Checkbox): TRUE/FALSE draw as a box, any other
         // value displays as General.
@@ -261,7 +263,8 @@ impl NumberFormat {
         let Some(mut out) = out else {
             return (Formatted { text: OVERFLOW.into(), color: sec.color, fill: None, numeric: true }, true);
         };
-        if minus && sec.kind != SecKind::Text {
+        // Excel drops the minus sign when the first section shows a negative number as all zeros.
+        if minus && sec.kind != SecKind::Text && !out.zero {
             out.prepend("-");
         }
         (Formatted { text: out.text, color: sec.color, fill: out.fill, numeric: true }, false)
@@ -294,6 +297,78 @@ pub fn format_value(v: &Value, fmt: &NumberFormat, sys: DateSystem) -> Formatted
     }
 }
 
+/// A small per-thread cache of parsed format codes for callers that format many values with the
+/// same code (`TEXT` over a range, chart labels). A parsed format depends on the code text only
+/// (the date system and values are applied when formatting), so the code is the whole key.
+mod parse_cache {
+    use std::cell::RefCell;
+    use std::collections::HashMap;
+
+    use super::NumberFormat;
+
+    /// Most codes kept per thread. A full cache is emptied, so memory stays bounded.
+    pub(super) const CAPACITY: usize = 64;
+    /// Longer codes are parsed every time and never stored.
+    pub(super) const MAX_CODE_LEN: usize = 256;
+
+    thread_local! {
+        static CACHE: RefCell<HashMap<String, NumberFormat>> = RefCell::new(HashMap::new());
+    }
+
+    pub(super) fn get(code: &str) -> NumberFormat {
+        if code.len() > MAX_CODE_LEN {
+            return NumberFormat::parse(code);
+        }
+        // Not usable (thread shutting down, re-entered): parse without the cache.
+        let cached = CACHE
+            .try_with(|c| {
+                let mut c = c.try_borrow_mut().ok()?;
+                if let Some(f) = c.get(code) {
+                    return Some(f.clone());
+                }
+                let f = NumberFormat::parse(code);
+                if c.len() >= CAPACITY {
+                    c.clear();
+                }
+                c.insert(code.to_string(), f.clone());
+                Some(f)
+            })
+            .ok()
+            .flatten();
+        cached.unwrap_or_else(|| NumberFormat::parse(code))
+    }
+
+    #[cfg(test)]
+    thread_local! {
+        static PARSES: std::cell::Cell<usize> = const { std::cell::Cell::new(0) };
+    }
+
+    #[cfg(test)]
+    pub(super) fn count_parse() {
+        let _ = PARSES.try_with(|p| p.set(p.get() + 1));
+    }
+
+    /// Parses done on this thread so far (tests only).
+    #[cfg(test)]
+    pub(super) fn parses() -> usize {
+        PARSES.try_with(std::cell::Cell::get).unwrap_or(0)
+    }
+
+    /// Empties this thread's cache (tests only).
+    #[cfg(test)]
+    pub(super) fn clear() {
+        let _ = CACHE.try_with(|c| c.borrow_mut().clear());
+    }
+}
+
+impl NumberFormat {
+    /// Like [`NumberFormat::parse`], but remembers recently parsed codes (per thread, bounded) so
+    /// formatting many values with one code parses it once. Same result as `parse`.
+    pub fn parse_cached(code: &str) -> NumberFormat {
+        parse_cache::get(code)
+    }
+}
+
 /// The `TEXT()` worksheet function: formats a value with a format code. Numeric text is
 /// converted to a number first; other text and booleans (as `TRUE`/`FALSE`) go through the text
 /// section, or are returned as is.
@@ -301,7 +376,7 @@ pub fn text_function(v: &Value, code: &str, sys: DateSystem) -> Result<String, C
     if code.is_empty() {
         return Ok(String::new());
     }
-    let fmt = NumberFormat::parse(code);
+    let fmt = NumberFormat::parse_cached(code);
     let n = match v.scalar() {
         Value::Error(e) => return Err(e),
         Value::Empty => 0.0,
diff --git a/crates/numfmt/src/parse.rs b/crates/numfmt/src/parse.rs
index e54f04c..6df22ad 100644
--- a/crates/numfmt/src/parse.rs
+++ b/crates/numfmt/src/parse.rs
@@ -513,6 +513,7 @@ fn analyze(raw: Raw) -> Section {
     let mut seen_exp = false;
     let mut seen_digit = false;
     let mut fraction_slash = false;
+    let scientific = toks.iter().skip_while(|t| !matches!(t, Tok::Digit(_))).any(|t| matches!(t, Tok::Exp { .. }));
     for i in 0..toks.len() {
         let Some(t) = toks.get(i).cloned() else { break };
         let replace = match t {
@@ -547,6 +548,10 @@ fn analyze(raw: Raw) -> Section {
                 if seen_digit && next_digit && !seen_point && !seen_exp {
                     sec.thousands = true;
                     Some(Tok::Lit(String::new()))
+                } else if seen_digit && scientific {
+                    // Observed: a scientific section never scales; any other comma after the
+                    // first digit shows nothing (`#,e+#`, `#e+#,`, `#e+000,00`).
+                    Some(Tok::Lit(String::new()))
                 } else if seen_digit && !next_digit {
                     sec.scale += 1;
                     Some(Tok::Lit(String::new()))
diff --git a/crates/numfmt/src/render.rs b/crates/numfmt/src/render.rs
index 7befe59..64a4fca 100644
--- a/crates/numfmt/src/render.rs
+++ b/crates/numfmt/src/render.rs
@@ -1,7 +1,7 @@
 //! Rendering a value with a parsed section.
 
 use gridcraft_core::DateSystem;
-use gridcraft_core::date::{MONTHS, WEEKDAYS, datetime_from_serial};
+use gridcraft_core::date::{MONTHS, WEEKDAYS, datetime_from_serial, max_serial};
 
 use crate::decimal::{decimal_digits, fixed, fixed_from_digits, format_general_fit};
 use crate::parse::{DatePart, Section, Tok};
@@ -11,6 +11,8 @@ use crate::parse::{DatePart, Section, Tok};
 pub(crate) struct Out {
     pub text: String,
     pub fill: Option<(char, usize)>,
+    /// True when every digit shown is zero (a number section that rounded to zero).
+    pub zero: bool,
 }
 
 impl Out {
@@ -58,7 +60,7 @@ pub(crate) fn render_general(sec: &Section, v: f64, width: usize) -> Out {
 
 /// Renders a date/time. `None` when the serial is outside the supported range.
 pub(crate) fn render_date(sec: &Section, v: f64, sys: DateSystem) -> Option<Out> {
-    if !v.is_finite() || !(0.0..2_958_466.0).contains(&v) {
+    if !v.is_finite() || !(0.0..max_serial(sys) as f64 + 1.0).contains(&v) {
         return None;
     }
     let sub_digits = sec.toks.iter().filter_map(|t| if let Tok::Date(DatePart::SubSec(n)) = t { Some(*n) } else { None }).max().unwrap_or(0).min(3);
@@ -231,7 +233,9 @@ fn digit_indices(toks: &[Tok], range: std::ops::Range<usize>) -> Vec<usize> {
 /// Renders a non-negative number through a number section.
 pub(crate) fn render_number(sec: &Section, v: f64) -> Out {
     let mut x = v.abs();
-    if sec.percent > 0 {
+    // Observed: `%` in a scientific section is only a literal (`#%e+#` shows 123456.789 as
+    // `1%e+5`).
+    if sec.percent > 0 && !sec.exp {
         x *= 100f64.powi(sec.percent.min(20));
     }
     if sec.scale > 0 {
@@ -247,6 +251,7 @@ pub(crate) fn render_number(sec: &Section, v: f64) -> Out {
     let mut pieces: Vec<String> = vec![String::new(); n];
     let mut before: Vec<String> = vec![String::new(); n + 1];
     let mut lits: Vec<Option<String>> = Vec::new();
+    let mut zero = false;
     if sec.fraction {
         lits = vec![None; n];
         render_fraction(sec, x, &mut pieces, &mut lits);
@@ -264,7 +269,9 @@ pub(crate) fn render_number(sec: &Section, v: f64) -> Out {
             let exp_idx = digit_indices(toks, e_at + 1..n);
             let step = int_idx.len().max(1) as i32;
             let (mut e, int_s, frac_s) = if x == 0.0 {
-                (0i32, String::new(), "0".repeat(frac_idx.len()))
+                // Observed: zero shows `0` in every integer placeholder, `#` and `?` too
+                // (`#.#E+#` gives `0.E+0`, `####.####E+#` gives `0000.E+0`).
+                (0i32, "0".repeat(int_idx.len()), "0".repeat(frac_idx.len()))
             } else {
                 let (digits, xe) = decimal_digits(x);
                 let mut e = xe - xe.rem_euclid(step);
@@ -283,26 +290,30 @@ pub(crate) fn render_number(sec: &Section, v: f64) -> Out {
             if int_s.is_empty() && frac_s.chars().all(|c| c == '0') {
                 e = 0;
             }
-            let mut head = String::from(if upper { "E" } else { "e" });
-            if e < 0 {
-                head.push('-');
+            let head = if upper { "E" } else { "e" };
+            let sign = if e < 0 {
+                "-"
             } else if plus {
-                head.push('+');
-            }
-            let width = exp_idx.iter().filter(|&&i| matches!(toks.get(i), Some(Tok::Digit('0')))).count().min(20);
-            let digits = format!("{:0w$}", e.unsigned_abs(), w = width);
+                "+"
+            } else {
+                ""
+            };
+            let digits = e.unsigned_abs().to_string();
+            // The sign sits right before the exponent digits, after any literal that follows the
+            // `E` (observed: `|0|e+|0|` shows `|1|e|+5|`); `?` pads the digits with spaces.
             match exp_idx.first() {
                 Some(&first) => {
                     if let Some(p) = pieces.get_mut(e_at) {
-                        *p = head;
+                        *p = head.to_string();
                     }
-                    if let Some(p) = pieces.get_mut(first) {
-                        *p = digits;
+                    if let Some(b) = before.get_mut(first) {
+                        *b = sign.to_string();
                     }
+                    fill_int(toks, &exp_idx, &digits, false, false, &mut pieces);
                 }
                 None => {
                     if let Some(p) = pieces.get_mut(e_at) {
-                        *p = head + &digits;
+                        *p = format!("{head}{sign}{digits}");
                     }
                 }
             }
@@ -310,6 +321,7 @@ pub(crate) fn render_number(sec: &Section, v: f64) -> Out {
         } else {
             fixed(x, frac_idx.len())
         };
+        zero = int_s.chars().chain(frac_s.chars()).all(|c| c == '0');
         fill_int(toks, &int_idx, &int_s, sec.thousands, false, &mut pieces);
         if int_idx.is_empty()
             && !int_s.is_empty()
@@ -338,6 +350,7 @@ pub(crate) fn render_number(sec: &Section, v: f64) -> Out {
             _ => out.push(pieces.get(i).map(String::as_str).unwrap_or("")),
         }
     }
+    out.zero = zero;
     out
 }
 
diff --git a/crates/numfmt/src/tests.rs b/crates/numfmt/src/tests.rs
index 6c2306c..c335ed8 100644
--- a/crates/numfmt/src/tests.rs
+++ b/crates/numfmt/src/tests.rs
@@ -24,7 +24,7 @@ fn numbers() {
     assert_eq!(f("0", -2.5), "-3");
     assert_eq!(f("0.00", 2.675), "2.68");
     assert_eq!(f("0.00", 1.005), "1.01");
-    assert_eq!(f("0.0", -0.04), "-0.0");
+    assert_eq!(f("0.0", -0.04), "0.0");
     assert_eq!(f("00000", 123.0), "00123");
     assert_eq!(f("000-00-0000", 123456789.0), "123-45-6789");
     assert_eq!(f("#.##", 0.5), ".5");
@@ -105,6 +105,29 @@ fn scientific() {
     assert_eq!(f("0.00E+00", -12345.0), "-1.23E+04");
 }
 
+/// A negative number that rounds to zero in the first section shows no minus sign; a negative
+/// section of its own keeps its text (observed Excel results).
+#[test]
+fn negative_rounding_to_zero_drops_the_sign() {
+    let cases: &[(&str, f64, &str)] = &[
+        ("0.00", -0.0033, "0.00"),
+        ("0.00", -2.89e-9, "0.00"),
+        ("0.00", -0.005, "-0.01"),
+        ("0", -0.4, "0"),
+        ("0", -0.5, "-1"),
+        ("0.0", -0.004, "0.0"),
+        ("#,##0.00", -0.004, "0.00"),
+        ("0.00%", -2.89e-9, "0.00%"),
+        ("0.00%", -0.0033, "-0.33%"),
+        ("0.00;(0.00)", -0.0033, "(0.00)"),
+        ("0.00;-0.00;\"zero\"", -0.0033, "-0.00"),
+        ("0.00E+00", -2.89e-9, "-2.89E-09"),
+    ];
+    for &(code, n, want) in cases {
+        assert_eq!(f(code, n), want, "{code} with {n}");
+    }
+}
+
 #[test]
 fn fractions() {
     assert_eq!(f("# ?/?", 1.5), "1 1/2");
@@ -247,6 +270,11 @@ fn dates_and_times() {
     assert_eq!(f("m/d/yyyy", 60.0), "2/29/1900");
     assert_eq!(f("m/d/yyyy", 0.0), "1/0/1900");
     assert_eq!(format_value(&Value::Number(0.0), &NumberFormat::parse("m/d/yyyy"), DateSystem::D1904).text, "1/1/1904");
+    let fmt = NumberFormat::parse("m/d/yyyy");
+    assert_eq!(format_value(&Value::Number(2957003.5), &fmt, DateSystem::D1904).text, "12/31/9999");
+    assert_eq!(format_value(&Value::Number(2957004.0), &fmt, DateSystem::D1904).text, "########");
+    assert_eq!(format_value(&Value::Number(2958465.0), &fmt, DateSystem::D1900).text, "12/31/9999");
+    assert_eq!(format_value(&Value::Number(2958466.0), &fmt, DateSystem::D1900).text, "########");
     assert_eq!(f("m/d/yyyy", -1.0), "########");
     assert_eq!(f("m/d/yyyy", 3e6), "########");
     assert_eq!(f("[$-409]m/d/yyyy", 46302.0), "10/7/2026");
@@ -339,7 +367,11 @@ fn text_fn() {
     assert_eq!(text_function(&Value::Empty, "0.00", S), Ok("0.00".into()));
     assert_eq!(text_function(&Value::Number(5.0), "", S), Ok("".into()));
     assert_eq!(text_function(&Value::Number(-1.0), "m/d/yyyy", S), Err(CellError::Value));
+    assert_eq!(text_function(&Value::Number(2957003.0), "m/d/yyyy", DateSystem::D1904), Ok("12/31/9999".into()));
+    assert_eq!(text_function(&Value::Number(2957004.0), "m/d/yyyy", DateSystem::D1904), Err(CellError::Value));
     assert_eq!(text_function(&Value::Bool(true), "0", S), Ok("TRUE".into()));
+    assert_eq!(text_function(&Value::Number(-0.0033), "0", S), Ok("0".into()));
+    assert_eq!(text_function(&Value::Number(-0.4), "0", S), Ok("0".into()));
     // Booleans go through the text section as TRUE/FALSE (observed Excel results).
     let cases: &[(bool, &str, &str)] = &[
         (true, ";;;@", "TRUE"),
@@ -582,3 +614,174 @@ fn decimal_digits_keeps_fifteen_digits_and_truncates_a_tie() {
     let (d, e) = decimal_digits(999999999999999.6);
     assert_eq!((d, e), ([1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], 15));
 }
+
+// ---- parse cache ----
+
+/// `TEXT()` as it was before the cache: parse the code, then format.
+fn text_uncached(v: &Value, code: &str, sys: DateSystem) -> Result<String, CellError> {
+    if code.is_empty() {
+        return Ok(String::new());
+    }
+    let fmt = NumberFormat::parse(code);
+    let n = match v.scalar() {
+        Value::Error(e) => return Err(e),
+        Value::Empty => 0.0,
+        Value::Number(n) => n,
+        Value::Bool(b) => return Ok(fmt.format_text(if b { "TRUE" } else { "FALSE" }).text),
+        Value::Text(t) => match gridcraft_core::parse::parse_number_text(&t) {
+            Some(n) => n,
+            None => return Ok(fmt.format_text(&t).text),
+        },
+        Value::Array(_) => return Err(CellError::Value),
+    };
+    if !n.is_finite() {
+        return Err(CellError::Num);
+    }
+    let (f, overflow) = fmt.format_number(n, sys);
+    if overflow { Err(CellError::Value) } else { Ok(f.text) }
+}
+
+const CACHE_CODES: &[&str] = &[
+    "0",
+    "0.00",
+    "#,##0.00",
+    "#,##0.00;[Red](#,##0.00)",
+    "$#,##0.00",
+    "0%",
+    "0.0%",
+    "0.00E+00",
+    "##0.0E+0",
+    "General",
+    "general",
+    "checkbox",
+    "@",
+    "0;@",
+    "0;-0;;@",
+    "00000",
+    "# ?/?",
+    "# ??/16",
+    "?/?",
+    "m/d/yyyy",
+    "yyyy-mm-dd hh:mm:ss",
+    "dddd, mmmm d, yyyy",
+    "h:mm AM/PM",
+    "[h]:mm:ss",
+    "mm:ss.000",
+    "[Red]0;[Blue]-0",
+    "[>100]0.0;[<5]0.000;0",
+    "[<=9999999]###-####;(###) ###-####",
+    "[$-409]d mmm yy",
+    "\"abc\"0",
+    "\\x0",
+    "*-0",
+    "_(* #,##0_)",
+    "0.0.0",
+    "[",
+    "\"abc",
+    "0;0;0;0;0",
+    "#,##0.00;[Red",
+    "[$-]0",
+    "  0.00  ",
+    "[Color99]0",
+    "0.00_);(0.00)",
+    "#,,\"M\"",
+    "yyyy",
+    "",
+];
+
+fn cache_values() -> Vec<Value> {
+    vec![
+        Value::Number(0.0),
+        Value::Number(1234.5678),
+        Value::Number(-42.5),
+        Value::Number(0.5),
+        Value::Number(45000.75),
+        Value::Number(1e15),
+        Value::Number(1e-7),
+        Value::Number(-0.0001),
+        Value::Number(f64::INFINITY),
+        Value::from("abc"),
+        Value::from("12.5"),
+        Value::Bool(true),
+        Value::Empty,
+        Value::Error(CellError::NA),
+    ]
+}
+
+#[test]
+fn parse_cached_gives_the_same_results_cold_and_warm() {
+    assert!(CACHE_CODES.len() >= 40);
+    parse_cache::clear();
+    let values = cache_values();
+    for sys in [DateSystem::D1900, DateSystem::D1904] {
+        // Cold on the first system, warm on the second.
+        for code in CACHE_CODES {
+            let direct = NumberFormat::parse(code);
+            let cached = NumberFormat::parse_cached(code);
+            assert_eq!(cached.code(), direct.code(), "{code:?}");
+            assert_eq!(
+                (cached.kind(), cached.is_date(), cached.is_text(), cached.is_general()),
+                (direct.kind(), direct.is_date(), direct.is_text(), direct.is_general())
+            );
+            for v in &values {
+                let want = text_uncached(v, code, sys);
+                assert_eq!(text_function(v, code, sys), want, "TEXT({v:?}, {code:?})");
+                // Again, now certainly warm.
+                assert_eq!(text_function(v, code, sys), want, "warm TEXT({v:?}, {code:?})");
+                assert_eq!(format_value(v, &cached, sys), format_value(v, &direct, sys), "{v:?} {code:?}");
+            }
+        }
+    }
+}
+
+#[test]
+fn parse_cached_parses_each_code_once() {
+    parse_cache::clear();
+    let before = parse_cache::parses();
+    for i in 0..10_000 {
+        assert!(text_function(&Value::Number(f64::from(i) + 0.5), "0.00", S).is_ok());
+    }
+    assert_eq!(parse_cache::parses() - before, 1);
+
+    let before = parse_cache::parses();
+    for i in 0..10_000 {
+        let code = if i % 2 == 0 { "0.00" } else { "#,##0.0" };
+        assert!(text_function(&Value::Number(f64::from(i)), code, S).is_ok());
+    }
+    // "0.00" is still cached from above: only the second code is new.
+    assert_eq!(parse_cache::parses() - before, 1);
+
+    parse_cache::clear();
+    let before = parse_cache::parses();
+    for i in 0..10_000 {
+        let code = if i % 2 == 0 { "0.00" } else { "#,##0.0" };
+        assert!(text_function(&Value::Number(f64::from(i)), code, S).is_ok());
+    }
+    assert_eq!(parse_cache::parses() - before, 2);
+}
+
+#[test]
+fn parse_cache_is_bounded() {
+    parse_cache::clear();
+    // More distinct codes than the capacity: all still format correctly...
+    let n = parse_cache::CAPACITY + 10;
+    for i in 0..n {
+        let c = format!("0.00\"{i}\"");
+        assert_eq!(text_function(&Value::Number(1.0), &c, S), Ok(format!("1.00{i}")));
+    }
+    // ...the first ones were evicted (parsed again), the newest is still cached.
+    let before = parse_cache::parses();
+    let newest = format!("0.00\"{}\"", n - 1);
+    assert!(text_function(&Value::Number(1.0), &newest, S).is_ok());
+    assert_eq!(parse_cache::parses() - before, 0);
+    assert!(text_function(&Value::Number(1.0), "0.00\"0\"", S).is_ok());
+    assert_eq!(parse_cache::parses() - before, 1);
+
+    // A very long code is parsed on every call and not stored.
+    let long = format!("0\"{}\"", "x".repeat(parse_cache::MAX_CODE_LEN));
+    let before = parse_cache::parses();
+    for _ in 0..3 {
+        assert!(text_function(&Value::Number(1.0), &long, S).is_ok());
+    }
+    assert_eq!(parse_cache::parses() - before, 3);
+}
diff --git a/crates/numfmt/tests/poi_number_format_approx.rs b/crates/numfmt/tests/poi_number_format_approx.rs
new file mode 100644
index 0000000..0f99321
--- /dev/null
+++ b/crates/numfmt/tests/poi_number_format_approx.rs
@@ -0,0 +1,272 @@
+//! `TEXT(value, format)` against the results Excel cached in Apache POI's
+//! `test-data/spreadsheet/NumberFormatApproxTests.xlsx` (sheet `Tests`: B = format, C = value,
+//! A = `=TEXT(C, B)`). The workbook is not committed; its rows are copied here as data.
+
+use gridcraft_core::{DateSystem, Value};
+use gridcraft_numfmt::text_function;
+
+/// (format, value, Excel's result).
+// The last row's 3.14159 is the workbook's value, not an approximation of pi.
+#[allow(clippy::approx_constant)]
+const CASES: &[(&str, f64, &str)] = &[
+    (r"|#,e-#|", 123456.789, r"|1e5|"),
+    (r"|#e-#,|", 123456.789, r"|1e5|"),
+    (r"|#%e-#|", 123456.789, r"|1%e5|"),
+    (r"|#e-#%|", 123456.789, r"|1e5%|"),
+    (r"|#|e-|#|", 123456.789, r"|1|e|5|"),
+    (r"|#.#|e-|#|", 123456.789, r"|1.2|e|5|"),
+    (r"|####.####|e-|#|", 123456.789, r"|12.3457|e|4|"),
+    (r"|#######.####|e-|#|", 123456.789, r"|123456.789|e|0|"),
+    (r"|#,######.####|e-|#|", 123456.789, r"|123,456.789|e|0|"),
+    (r"|0|e-|0|", 123456.789, r"|1|e|5|"),
+    (r"|0.0|e-|0|", 123456.789, r"|1.2|e|5|"),
+    (r"|0000.0000|e-|0|", 123456.789, r"|0012.3457|e|4|"),
+    (r"|0000000.0000|e-|0|", 123456.789, r"|0123456.7890|e|0|"),
+    (r"|0,000000.0000|e-|0|", 123456.789, r"|0,123,456.7890|e|0|"),
+    (r"|?|e-|?|", 123456.789, r"|1|e|5|"),
+    (r"|?.?|e-|?|", 123456.789, r"|1.2|e|5|"),
+    (r"|????.????|e-|?|", 123456.789, r"|  12.3457|e|4|"),
+    (r"|???????.????|e-|?|", 123456.789, r"| 123456.789 |e|0|"),
+    (r"|?,??????.????|e-|?|", 123456.789, r"|  123,456.789 |e|0|"),
+    (r"|#,e+#|", 123456.789, r"|1e+5|"),
+    (r"|#e+#,|", 123456.789, r"|1e+5|"),
+    (r"|#%e+#|", 123456.789, r"|1%e+5|"),
+    (r"|#e+#%|", 123456.789, r"|1e+5%|"),
+    (r"|#|e+|#|", 123456.789, r"|1|e|+5|"),
+    (r"|#.#|e+|#|", 123456.789, r"|1.2|e|+5|"),
+    (r"|####.####|e+|#|", 123456.789, r"|12.3457|e|+4|"),
+    (r"|#######.####|e+|#|", 123456.789, r"|123456.789|e|+0|"),
+    (r"|#,######.####|e+|#|", 123456.789, r"|123,456.789|e|+0|"),
+    (r"|0|e+|0|", 123456.789, r"|1|e|+5|"),
+    (r"|0.0|e+|0|", 123456.789, r"|1.2|e|+5|"),
+    (r"|0000.0000|e+|0|", 123456.789, r"|0012.3457|e|+4|"),
+    (r"|0000000.0000|e+|0|", 123456.789, r"|0123456.7890|e|+0|"),
+    (r"|0,000000.0000|e+|0|", 123456.789, r"|0,123,456.7890|e|+0|"),
+    (r"|?|e+|?|", 123456.789, r"|1|e|+5|"),
+    (r"|?.?|e+|?|", 123456.789, r"|1.2|e|+5|"),
+    (r"|????.????|e+|?|", 123456.789, r"|  12.3457|e|+4|"),
+    (r"|???????.????|e+|?|", 123456.789, r"| 123456.789 |e|+0|"),
+    (r"|?,??????.????|e+|?|", 123456.789, r"|  123,456.789 |e|+0|"),
+    (r"|#.#|E-|#|", 123456.789, r"|1.2|E|5|"),
+    (r"|#.#|E+|#|", 123456.789, r"|1.2|E|+5|"),
+    (r"|#,e-#|", 1.23456789e-05, r"|1e-5|"),
+    (r"|#e-#,|", 1.23456789e-05, r"|1e-5|"),
+    (r"|#%e-#|", 1.23456789e-05, r"|1%e-5|"),
+    (r"|#e-#%|", 1.23456789e-05, r"|1e-5%|"),
+    (r"|#|e-|#|", 1.23456789e-05, r"|1|e|-5|"),
+    (r"|#.#|e-|#|", 1.23456789e-05, r"|1.2|e|-5|"),
+    (r"|####.####|e-|#|", 1.23456789e-05, r"|1234.5679|e|-8|"),
+    (r"|#######.####|e-|#|", 1.23456789e-05, r"|123.4568|e|-7|"),
+    (r"|#,######.####|e-|#|", 1.23456789e-05, r"|123.4568|e|-7|"),
+    (r"|0|e-|0|", 1.23456789e-05, r"|1|e|-5|"),
+    (r"|0.0|e-|0|", 1.23456789e-05, r"|1.2|e|-5|"),
+    (r"|0000.0000|e-|0|", 1.23456789e-05, r"|1234.5679|e|-8|"),
+    (r"|0000000.0000|e-|0|", 1.23456789e-05, r"|0000123.4568|e|-7|"),
+    (r"|0,000000.0000|e-|0|", 1.23456789e-05, r"|0,000,123.4568|e|-7|"),
+    (r"|?|e-|?|", 1.23456789e-05, r"|1|e|-5|"),
+    (r"|?.?|e-|?|", 1.23456789e-05, r"|1.2|e|-5|"),
+    (r"|????.????|e-|?|", 1.23456789e-05, r"|1234.5679|e|-8|"),
+    (r"|???????.????|e-|?|", 1.23456789e-05, r"|    123.4568|e|-7|"),
+    (r"|?,??????.????|e-|?|", 1.23456789e-05, r"|      123.4568|e|-7|"),
+    (r"|#,e+#|", 1.23456789e-05, r"|1e-5|"),
+    (r"|#e+#,|", 1.23456789e-05, r"|1e-5|"),
+    (r"|#%e+#|", 1.23456789e-05, r"|1%e-5|"),
+    (r"|#e+#%|", 1.23456789e-05, r"|1e-5%|"),
+    (r"|#|e+|#|", 1.23456789e-05, r"|1|e|-5|"),
+    (r"|#.#|e+|#|", 1.23456789e-05, r"|1.2|e|-5|"),
+    (r"|#.####|e+|#|", 0.000123456789, r"|1.2346|e|-4|"),
+    (r"|##.####|e+|#|", 0.000123456789, r"|1.2346|e|-4|"),
+    (r"|###.####|e+|#|", 0.000123456789, r"|123.4568|e|-6|"),
+    (r"|####.####|e+|#|", 0.000123456789, r"|1.2346|e|-4|"),
+    (r"|#####.####|e+|#|", 0.000123456789, r"|12.3457|e|-5|"),
+    (r"|#######.####|e+|#|", 0.000123456789, r"|1234.5679|e|-7|"),
+    (r"|#.####|e+|#|", 1.23456789e-05, r"|1.2346|e|-5|"),
+    (r"|##.####|e+|#|", 1.23456789e-05, r"|12.3457|e|-6|"),
+    (r"|###.####|e+|#|", 1.23456789e-05, r"|12.3457|e|-6|"),
+    (r"|####.####|e+|#|", 1.23456789e-05, r"|1234.5679|e|-8|"),
+    (r"|#####.####|e+|#|", 1.23456789e-05, r"|1.2346|e|-5|"),
+    (r"|#######.####|e+|#|", 1.23456789e-05, r"|123.4568|e|-7|"),
+    (r"|#.####|e+|#|", 1.23456789e-06, r"|1.2346|e|-6|"),
+    (r"|##.####|e+|#|", 1.23456789e-06, r"|1.2346|e|-6|"),
+    (r"|###.####|e+|#|", 1.23456789e-06, r"|1.2346|e|-6|"),
+    (r"|####.####|e+|#|", 1.23456789e-06, r"|123.4568|e|-8|"),
+    (r"|#####.####|e+|#|", 1.23456789e-06, r"|12345.6789|e|-10|"),
+    (r"|#######.####|e+|#|", 1.23456789e-06, r"|12.3457|e|-7|"),
+    (r"|#,######.####|e+|#|", 1.23456789e-06, r"|12.3457|e|-7|"),
+    (r"|0|e+|0|", 1.23456789e-05, r"|1|e|-5|"),
+    (r"|0.0|e+|0|", 1.23456789e-05, r"|1.2|e|-5|"),
+    (r"|0000.0000|e+|0|", 1.23456789e-05, r"|1234.5679|e|-8|"),
+    (r"|0000000.0000|e+|0|", 1.23456789e-05, r"|0000123.4568|e|-7|"),
+    (r"|0,000000.0000|e+|0|", 1.23456789e-05, r"|0,000,123.4568|e|-7|"),
+    (r"|?|e+|?|", 1.23456789e-05, r"|1|e|-5|"),
+    (r"|?.?|e+|?|", 1.23456789e-05, r"|1.2|e|-5|"),
+    (r"|????.????|e+|?|", 1.23456789e-05, r"|1234.5679|e|-8|"),
+    (r"|???????.????|e+|?|", 1.23456789e-05, r"|    123.4568|e|-7|"),
+    (r"|?,??????.????|e+|?|", 1.23456789e-05, r"|      123.4568|e|-7|"),
+    (r"|#.#|E-|#|", 1.23456789e-05, r"|1.2|E|-5|"),
+    (r"|#.#|E+|#|", 1.23456789e-05, r"|1.2|E|-5|"),
+    (r"|#,e-#|", 0.0, r"|0e0|"),
+    (r"|#e-#,|", 0.0, r"|0e0|"),
+    (r"|#%e-#|", 0.0, r"|0%e0|"),
+    (r"|#e-#%|", 0.0, r"|0e0%|"),
+    (r"|#|e-|#|", 0.0, r"|0|e|0|"),
+    (r"|#.#|e-|#|", 0.0, r"|0.|e|0|"),
+    (r"|####.####|e-|#|", 0.0, r"|0000.|e|0|"),
+    (r"|#######.####|e-|#|", 0.0, r"|0000000.|e|0|"),
+    (r"|#,######.####|e-|#|", 0.0, r"|0,000,000.|e|0|"),
+    (r"|0|e-|0|", 0.0, r"|0|e|0|"),
+    (r"|0.0|e-|0|", 0.0, r"|0.0|e|0|"),
+    (r"|0000.0000|e-|0|", 0.0, r"|0000.0000|e|0|"),
+    (r"|0000000.0000|e-|0|", 0.0, r"|0000000.0000|e|0|"),
+    (r"|0,000000.0000|e-|0|", 0.0, r"|0,000,000.0000|e|0|"),
+    (r"|?|e-|?|", 0.0, r"|0|e|0|"),
+    (r"|?.?|e-|?|", 0.0, r"|0. |e|0|"),
+    (r"|????.????|e-|?|", 0.0, r"|0000.    |e|0|"),
+    (r"|???????.????|e-|?|", 0.0, r"|0000000.    |e|0|"),
+    (r"|?,??????.????|e-|?|", 0.0, r"|0,000,000.    |e|0|"),
+    (r"|#,e+#|", 0.0, r"|0e+0|"),
+    (r"|#e+#,|", 0.0, r"|0e+0|"),
+    (r"|#%e+#|", 0.0, r"|0%e+0|"),
+    (r"|#e+#%|", 0.0, r"|0e+0%|"),
+    (r"|#|e+|#|", 0.0, r"|0|e|+0|"),
+    (r"|#.#|e+|#|", 0.0, r"|0.|e|+0|"),
+    (r"|####.####|e+|#|", 0.0, r"|0000.|e|+0|"),
+    (r"|#######.####|e+|#|", 0.0, r"|0000000.|e|+0|"),
+    (r"|#,######.####|e+|#|", 0.0, r"|0,000,000.|e|+0|"),
+    (r"|0|e+|0|", 0.0, r"|0|e|+0|"),
+    (r"|0.0|e+|0|", 0.0, r"|0.0|e|+0|"),
+    (r"|0000.0000|e+|0|", 0.0, r"|0000.0000|e|+0|"),
+    (r"|0000000.0000|e+|0|", 0.0, r"|0000000.0000|e|+0|"),
+    (r"|0,000000.0000|e+|0|", 0.0, r"|0,000,000.0000|e|+0|"),
+    (r"|?|e+|?|", 0.0, r"|0|e|+0|"),
+    (r"|?.?|e+|?|", 0.0, r"|0. |e|+0|"),
+    (r"|????.????|e+|?|", 0.0, r"|0000.    |e|+0|"),
+    (r"|???????.????|e+|?|", 0.0, r"|0000000.    |e|+0|"),
+    (r"|?,??????.????|e+|?|", 0.0, r"|0,000,000.    |e|+0|"),
+    (r"|#.#|E-|#|", 0.0, r"|0.|E|0|"),
+    (r"|#.#|E+|#|", 0.0, r"|0.|E|+0|"),
+    (r"|#,e-#|", -123456.789, r"-|1e5|"),
+    (r"|#e-#,|", -123456.789, r"-|1e5|"),
+    (r"|#%e-#|", -123456.789, r"-|1%e5|"),
+    (r"|#e-#%|", -123456.789, r"-|1e5%|"),
+    (r"|#|e-|#|", -123456.789, r"-|1|e|5|"),
+    (r"|#.#|e-|#|", -123456.789, r"-|1.2|e|5|"),
+    (r"|####.####|e-|#|", -123456.789, r"-|12.3457|e|4|"),
+    (r"|#######.####|e-|#|", -123456.789, r"-|123456.789|e|0|"),
+    (r"|#,######.####|e-|#|", -123456.789, r"-|123,456.789|e|0|"),
+    (r"|0|e-|0|", -123456.789, r"-|1|e|5|"),
+    (r"|0.0|e-|0|", -123456.789, r"-|1.2|e|5|"),
+    (r"|0000.0000|e-|0|", -123456.789, r"-|0012.3457|e|4|"),
+    (r"|0000000.0000|e-|0|", -123456.789, r"-|0123456.7890|e|0|"),
+    (r"|0,000000.0000|e-|0|", -123456.789, r"-|0,123,456.7890|e|0|"),
+    (r"|?|e-|?|", -123456.789, r"-|1|e|5|"),
+    (r"|?.?|e-|?|", -123456.789, r"-|1.2|e|5|"),
+    (r"|????.????|e-|?|", -123456.789, r"-|  12.3457|e|4|"),
+    (r"|???????.????|e-|?|", -123456.789, r"-| 123456.789 |e|0|"),
+    (r"|?,??????.????|e-|?|", -123456.789, r"-|  123,456.789 |e|0|"),
+    (r"|#,e+#|", -123456.789, r"-|1e+5|"),
+    (r"|#e+#,|", -123456.789, r"-|1e+5|"),
+    (r"|#%e+#|", -123456.789, r"-|1%e+5|"),
+    (r"|#e+#%|", -123456.789, r"-|1e+5%|"),
+    (r"|#|e+|#|", -123456.789, r"-|1|e|+5|"),
+    (r"|#.#|e+|#|", -123456.789, r"-|1.2|e|+5|"),
+    (r"|####.####|e+|#|", -123456.789, r"-|12.3457|e|+4|"),
+    (r"|#######.####|e+|#|", -123456.789, r"-|123456.789|e|+0|"),
+    (r"|#,######.####|e+|#|", -123456.789, r"-|123,456.789|e|+0|"),
+    (r"|0|e+|0|", -123456.789, r"-|1|e|+5|"),
+    (r"|0.0|e+|0|", -123456.789, r"-|1.2|e|+5|"),
+    (r"|0000.0000|e+|0|", -123456.789, r"-|0012.3457|e|+4|"),
+    (r"|0000000.0000|e+|0|", -123456.789, r"-|0123456.7890|e|+0|"),
+    (r"|0,000000.0000|e+|0|", -123456.789, r"-|0,123,456.7890|e|+0|"),
+    (r"|?|e+|?|", -123456.789, r"-|1|e|+5|"),
+    (r"|?.?|e+|?|", -123456.789, r"-|1.2|e|+5|"),
+    (r"|????.????|e+|?|", -123456.789, r"-|  12.3457|e|+4|"),
+    (r"|???????.????|e+|?|", -123456.789, r"-| 123456.789 |e|+0|"),
+    (r"|?,??????.????|e+|?|", -123456.789, r"-|  123,456.789 |e|+0|"),
+    (r"|#.#|E-|#|", -123456.789, r"-|1.2|E|5|"),
+    (r"|#.#|E+|#|", -123456.789, r"-|1.2|E|+5|"),
+    (r"|#,e-#|", -1.23456789e-05, r"-|1e-5|"),
+    (r"|#e-#,|", -1.23456789e-05, r"-|1e-5|"),
+    (r"|#%e-#|", -1.23456789e-05, r"-|1%e-5|"),
+    (r"|#e-#%|", -1.23456789e-05, r"-|1e-5%|"),
+    (r"|#|e-|#|", -1.23456789e-05, r"-|1|e|-5|"),
+    (r"|#.#|e-|#|", -1.23456789e-05, r"-|1.2|e|-5|"),
+    (r"|####.####|e-|#|", -1.23456789e-05, r"-|1234.5679|e|-8|"),
+    (r"|#######.####|e-|#|", -1.23456789e-05, r"-|123.4568|e|-7|"),
+    (r"|#,######.####|e-|#|", -1.23456789e-05, r"-|123.4568|e|-7|"),
+    (r"|0|e-|0|", -1.23456789e-05, r"-|1|e|-5|"),
+    (r"|0.0|e-|0|", -1.23456789e-05, r"-|1.2|e|-5|"),
+    (r"|0000.0000|e-|0|", -1.23456789e-05, r"-|1234.5679|e|-8|"),
+    (r"|0000000.0000|e-|0|", -1.23456789e-05, r"-|0000123.4568|e|-7|"),
+    (r"|0,000000.0000|e-|0|", -1.23456789e-05, r"-|0,000,123.4568|e|-7|"),
+    (r"|?|e-|?|", -1.23456789e-05, r"-|1|e|-5|"),
+    (r"|?.?|e-|?|", -1.23456789e-05, r"-|1.2|e|-5|"),
+    (r"|????.????|e-|?|", -1.23456789e-05, r"-|1234.5679|e|-8|"),
+    (r"|???????.????|e-|?|", -1.23456789e-05, r"-|    123.4568|e|-7|"),
+    (r"|?,??????.????|e-|?|", -1.23456789e-05, r"-|      123.4568|e|-7|"),
+    (r"|#,e+#|", -1.23456789e-05, r"-|1e-5|"),
+    (r"|#e+#,|", -1.23456789e-05, r"-|1e-5|"),
+    (r"|#%e+#|", -1.23456789e-05, r"-|1%e-5|"),
+    (r"|#e+#%|", -1.23456789e-05, r"-|1e-5%|"),
+    (r"|#|e+|#|", -1.23456789e-05, r"-|1|e|-5|"),
+    (r"|#.#|e+|#|", -1.23456789e-05, r"-|1.2|e|-5|"),
+    (r"|####.####|e+|#|", -1.23456789e-05, r"-|1234.5679|e|-8|"),
+    (r"|#######.####|e+|#|", -1.23456789e-05, r"-|123.4568|e|-7|"),
+    (r"|#,######.####|e+|#|", -1.23456789e-05, r"-|123.4568|e|-7|"),
+    (r"|0|e+|0|", -1.23456789e-05, r"-|1|e|-5|"),
+    (r"|0.0|e+|0|", -1.23456789e-05, r"-|1.2|e|-5|"),
+    (r"|0000.0000|e+|0|", -1.23456789e-05, r"-|1234.5679|e|-8|"),
+    (r"|0000000.0000|e+|0|", -1.23456789e-05, r"-|0000123.4568|e|-7|"),
+    (r"|0,000000.0000|e+|0|", -1.23456789e-05, r"-|0,000,123.4568|e|-7|"),
+    (r"|?|e+|?|", -1.23456789e-05, r"-|1|e|-5|"),
+    (r"|?.?|e+|?|", -1.23456789e-05, r"-|1.2|e|-5|"),
+    (r"|????.????|e+|?|", -1.23456789e-05, r"-|1234.5679|e|-8|"),
+    (r"|???????.????|e+|?|", -1.23456789e-05, r"-|    123.4568|e|-7|"),
+    (r"|?,??????.????|e+|?|", -1.23456789e-05, r"-|      123.4568|e|-7|"),
+    (r"|#.#|E-|#|", -1.23456789e-05, r"-|1.2|E|-5|"),
+    (r"|#.#|E+|#|", -1.23456789e-05, r"-|1.2|E|-5|"),
+    (r"|#.#|e+|#|", 1.2345678e+142, r"|1.2|e|+142|"),
+    (r"|#.#|e+|#####|", 1.2345678e+142, r"|1.2|e|+142|"),
+    (r"|#.#|e+|0|", 1.2345678e+142, r"|1.2|e|+142|"),
+    (r"|#.#|e+|000|", 1.2345678e+142, r"|1.2|e|+142|"),
+    (r"|#.#|e+|0000|", 1.2345678e+142, r"|1.2|e|+0142|"),
+    (r"|#.#|e+|00000|", 1.2345678e+142, r"|1.2|e|+00142|"),
+    (r"|#.#|e+|?|", 1.2345678e+142, r"|1.2|e|+142|"),
+    (r"|#.#|e+|???|", 1.2345678e+142, r"|1.2|e|+142|"),
+    (r"|#.#|e+|????|", 1.2345678e+142, r"|1.2|e|+ 142|"),
+    (r"|#.#|e+|?????|", 1.2345678e+142, r"|1.2|e|+  142|"),
+    (r"|#.#|e+|#|", 0.0, r"|0.|e|+0|"),
+    (r"|#.#|e+|#####|", 0.0, r"|0.|e|+0|"),
+    (r"|#.#|e+|0|", 0.0, r"|0.|e|+0|"),
+    (r"|#.#|e+|000|", 0.0, r"|0.|e|+000|"),
+    (r"|#.#|e+|0000|", 0.0, r"|0.|e|+0000|"),
+    (r"|#.#|e+|00000|", 0.0, r"|0.|e|+00000|"),
+    (r"|#.#|e+|?|", 0.0, r"|0.|e|+0|"),
+    (r"|#.#|e+|???|", 0.0, r"|0.|e|+  0|"),
+    (r"|#.#|e+|????|", 0.0, r"|0.|e|+   0|"),
+    (r"|#.#|e+|?????|", 0.0, r"|0.|e|+    0|"),
+    (r"|#.#|e+|#|", 1.2345678e-142, r"|1.2|e|-142|"),
+    (r"|#.#|e+|#####|", 1.2345678e-142, r"|1.2|e|-142|"),
+    (r"|#.#|e+|0|", 1.2345678e-142, r"|1.2|e|-142|"),
+    (r"|#.#|e+|000|", 1.2345678e-142, r"|1.2|e|-142|"),
+    (r"|#.#|e+|0000|", 1.2345678e-142, r"|1.2|e|-0142|"),
+    (r"|#.#|e+|00000|", 1.2345678e-142, r"|1.2|e|-00142|"),
+    (r"|#.#|e+|000,00|", 1.2345678e-142, r"|1.2|e|-00142|"),
+    (r"|#.#|e+|?|", 1.2345678e-142, r"|1.2|e|-142|"),
+    (r"|#.#|e+|???|", 1.2345678e-142, r"|1.2|e|-142|"),
+    (r"|#.#|e+|????|", 1.2345678e-142, r"|1.2|e|- 142|"),
+    (r"|#.#|e+|?????|", 1.2345678e-142, r"|1.2|e|-  142|"),
+    (r"#,##0.00e+00", 3.14159, r"3.14e+00"),
+];
+
+#[test]
+fn poi_number_format_approx_tests() {
+    let wrong: Vec<String> = CASES
+        .iter()
+        .filter_map(|&(code, v, want)| {
+            let got = text_function(&Value::Number(v), code, DateSystem::D1900);
+            (got.as_deref() != Ok(want)).then(|| format!("TEXT({v}, {code:?}) = {got:?}, Excel {want:?}"))
+        })
+        .collect();
+    assert!(wrong.is_empty(), "{} of {} cases differ:\n{}", wrong.len(), CASES.len(), wrong.join("\n"));
+}
diff --git a/crates/pdf/src/lib.rs b/crates/pdf/src/lib.rs
index 51c2df1..b55f247 100644
--- a/crates/pdf/src/lib.rs
+++ b/crates/pdf/src/lib.rs
@@ -145,7 +145,8 @@ impl Font {
 
 /// Width of `text` in points when set in `font` at `size` points.
 pub fn text_width(font: Font, size: f32, text: &str) -> f32 {
-    let units: u32 = text.chars().map(|c| font.char_width(c) as u32).sum();
+    // u64: a u32 sum overflows for ~8 million characters.
+    let units: u64 = text.chars().map(|c| u64::from(font.char_width(c))).sum();
     units as f32 * size / 1000.0
 }
 
@@ -221,6 +222,32 @@ fn n(v: f32) -> String {
     }
 }
 
+/// True when every value is finite (NaN and infinities are rejected).
+fn finite(v: &[f32]) -> bool {
+    v.iter().all(|x| x.is_finite())
+}
+
+/// A positive, finite extent (a width, height or radius).
+fn extent(v: f32) -> bool {
+    v > 0.0 && v.is_finite()
+}
+
+/// A stroke width: negative, NaN and infinite become 0 (the thinnest line).
+fn stroke_width(w: f32) -> f32 {
+    if w.is_finite() { w.max(0.0) } else { 0.0 }
+}
+
+/// The entries of a dash array (`[on, off, …]`, at most 8). A pattern the PDF specification
+/// forbids (any non-finite entry, or no entry that survives rounding to a positive number) is
+/// replaced by an empty array, i.e. a solid line.
+fn dash_values(dash: &[f32]) -> String {
+    let d: Vec<f32> = dash.iter().take(8).map(|v| if v.is_finite() { v.max(0.0) } else { f32::NAN }).collect();
+    if !finite(&d) || !d.iter().any(|v| (v.min(1.0e7) * 1000.0).round() > 0.0) {
+        return String::new();
+    }
+    d.iter().map(|v| n(*v)).collect::<Vec<_>>().join(" ")
+}
+
 fn rgb_op(c: Rgb, stroke: bool) -> String {
     let f = |v: u8| n(v as f32 / 255.0);
     format!("{} {} {} {}", f(c[0]), f(c[1]), f(c[2]), if stroke { "RG" } else { "rg" })
@@ -288,7 +315,7 @@ impl Page {
     }
 
     pub fn fill_rect(&mut self, x: f32, y: f32, w: f32, h: f32, color: Rgb) {
-        if w <= 0.0 || h <= 0.0 {
+        if !(extent(w) && extent(h) && finite(&[x, y])) {
             return;
         }
         let s = format!("{}\n{} {} {} {} re f", rgb_op(color, false), n(x), n(self.y(y + h)), n(w), n(h));
@@ -296,7 +323,10 @@ impl Page {
     }
 
     pub fn rect_stroke(&mut self, x: f32, y: f32, w: f32, h: f32, width: f32, color: Rgb) {
-        let s = format!("{}\n{} w [] 0 d\n{} {} {} {} re S", rgb_op(color, true), n(width), n(x), n(self.y(y + h)), n(w), n(h));
+        if !finite(&[x, y, w, h]) {
+            return;
+        }
+        let s = format!("{}\n{} w [] 0 d\n{} {} {} {} re S", rgb_op(color, true), n(stroke_width(width)), n(x), n(self.y(y + h)), n(w), n(h));
         self.op(&s);
     }
 
@@ -306,19 +336,28 @@ impl Page {
 
     /// A line with a dash pattern (`[on, off, …]` in points; empty = solid).
     pub fn stroke_line_dashed(&mut self, x0: f32, y0: f32, x1: f32, y1: f32, width: f32, color: Rgb, dash: &[f32]) {
-        let d: Vec<String> = dash.iter().take(8).map(|v| n(v.max(0.0))).collect();
-        let s =
-            format!("{}\n{} w [{}] 0 d\n{} {} m {} {} l S", rgb_op(color, true), n(width), d.join(" "), n(x0), n(self.y(y0)), n(x1), n(self.y(y1)));
+        if !finite(&[x0, y0, x1, y1]) {
+            return;
+        }
+        let s = format!(
+            "{}\n{} w [{}] 0 d\n{} {} m {} {} l S",
+            rgb_op(color, true),
+            n(stroke_width(width)),
+            dash_values(dash),
+            n(x0),
+            n(self.y(y0)),
+            n(x1),
+            n(self.y(y1))
+        );
         self.op(&s);
     }
 
     /// An open polyline.
     pub fn polyline(&mut self, pts: &[[f32; 2]], width: f32, color: Rgb, dash: &[f32]) {
-        if pts.len() < 2 {
+        if pts.len() < 2 || !pts.iter().all(|p| finite(p)) {
             return;
         }
-        let d: Vec<String> = dash.iter().take(8).map(|v| n(v.max(0.0))).collect();
-        let mut s = format!("{}\n{} w [{}] 0 d 1 j\n", rgb_op(color, true), n(width), d.join(" "));
+        let mut s = format!("{}\n{} w [{}] 0 d 1 j\n", rgb_op(color, true), n(stroke_width(width)), dash_values(dash));
         self.path(&mut s, pts, false);
         s.push_str(" S");
         self.op(&s);
@@ -335,7 +374,7 @@ impl Page {
 
     /// A closed polygon, filled and/or stroked.
     pub fn polygon(&mut self, pts: &[[f32; 2]], fill: Option<Rgb>, stroke: Option<(Rgb, f32)>) {
-        if pts.len() < 2 || (fill.is_none() && stroke.is_none()) {
+        if pts.len() < 2 || (fill.is_none() && stroke.is_none()) || !pts.iter().all(|p| finite(p)) {
             return;
         }
         let mut s = String::new();
@@ -344,7 +383,7 @@ impl Page {
             s.push('\n');
         }
         if let Some((c, w)) = stroke {
-            let _ = writeln!(s, "{}\n{} w [] 0 d 1 j", rgb_op(c, true), n(w));
+            let _ = writeln!(s, "{}\n{} w [] 0 d 1 j", rgb_op(c, true), n(stroke_width(w)));
         }
         self.path(&mut s, pts, true);
         s.push_str(match (fill.is_some(), stroke.is_some()) {
@@ -357,7 +396,7 @@ impl Page {
 
     /// A circle approximated by four cubic Béziers.
     pub fn circle(&mut self, cx: f32, cy: f32, r: f32, fill: Option<Rgb>, stroke: Option<(Rgb, f32)>) {
-        if r <= 0.0 || (fill.is_none() && stroke.is_none()) {
+        if !extent(r) || !finite(&[cx, cy]) || (fill.is_none() && stroke.is_none()) {
             return;
         }
         const K: f32 = 0.552_284_8;
@@ -369,7 +408,7 @@ impl Page {
             s.push('\n');
         }
         if let Some((c, w)) = stroke {
-            let _ = writeln!(s, "{}\n{} w [] 0 d", rgb_op(c, true), n(w));
+            let _ = writeln!(s, "{}\n{} w [] 0 d", rgb_op(c, true), n(stroke_width(w)));
         }
         let _ = write!(
             s,
@@ -417,7 +456,7 @@ impl Page {
     /// Text rotated by `angle` radians (clockwise on the page, like the y-down coordinate
     /// system) about its baseline origin.
     pub fn text_rotated(&mut self, x: f32, y: f32, size: f32, font: Font, color: Rgb, text: &str, angle: f32) {
-        if text.is_empty() || !(size.is_finite() && size > 0.0) {
+        if text.is_empty() || !extent(size) || !finite(&[x, y]) {
             return;
         }
         let fi = font.index();
@@ -446,7 +485,7 @@ impl Page {
     /// `(x, y, w, h)`. Malformed or oversized buffers are ignored.
     pub fn image_rgba(&mut self, x: f32, y: f32, w: f32, h: f32, rgba: &[u8], pw: u32, ph: u32) {
         let px = pw as u64 * ph as u64;
-        if pw == 0 || ph == 0 || px > MAX_IMAGE_PIXELS || (rgba.len() as u64) < px * 4 || w <= 0.0 || h <= 0.0 {
+        if pw == 0 || ph == 0 || px > MAX_IMAGE_PIXELS || (rgba.len() as u64) < px * 4 || !(extent(w) && extent(h) && finite(&[x, y])) {
             return;
         }
         let px = px as usize;
@@ -516,8 +555,23 @@ fn run_length(data: &[u8]) -> Vec<u8> {
     out
 }
 
-fn pdf_text_string(s: &str) -> String {
-    pdf_string(s)
+/// Longest Info string written, in characters; longer values are cut on a character boundary.
+const MAX_INFO_CHARS: usize = 1024;
+
+/// A PDF text string (document Info entries) for `text`: a literal `( … )` for printable ASCII,
+/// otherwise UTF-16BE with a byte-order mark as a hex string (ISO 32000-1 7.9.2.2).
+fn pdf_text_string(text: &str) -> String {
+    let text: String = text.chars().take(MAX_INFO_CHARS).collect();
+    if text.chars().all(|c| matches!(c, ' '..='~')) {
+        return pdf_string(&text);
+    }
+    let mut s = String::with_capacity(text.len() * 4 + 6);
+    s.push_str("<FEFF");
+    for unit in text.encode_utf16() {
+        let _ = write!(s, "{unit:04X}");
+    }
+    s.push('>');
+    s
 }
 
 impl PdfDoc {
diff --git a/crates/pdf/src/tests.rs b/crates/pdf/src/tests.rs
index e7b488a..6483cc7 100644
--- a/crates/pdf/src/tests.rs
+++ b/crates/pdf/src/tests.rs
@@ -157,3 +157,121 @@ fn hostile_inputs_never_panic() {
     let pdf = d.finish();
     check_xref(&pdf);
 }
+
+fn page_content(d: &PdfDoc) -> &str {
+    &d.pages[0].content
+}
+
+#[test]
+fn text_width_does_not_overflow() {
+    // 8,000,000 x 556 units exceeds u32::MAX: a u32 sum panics in debug builds.
+    let long = "a".repeat(8_000_000);
+    let w = text_width(Font::Helvetica, 10.0, &long);
+    assert!(w.is_finite() && w > 0.0);
+    assert!(w > text_width(Font::Helvetica, 10.0, &"a".repeat(7_000_000)));
+}
+
+#[test]
+fn all_zero_dash_is_drawn_solid() {
+    let mut d = PdfDoc::new();
+    let p = d.add_page(100.0, 100.0);
+    p.stroke_line_dashed(0.0, 0.0, 50.0, 0.0, 1.0, [0, 0, 0], &[0.0, 0.0]);
+    p.polyline(&[[0.0, 0.0], [5.0, 5.0]], 1.0, [0, 0, 0], &[0.0, 0.0001, f32::NAN]);
+    p.stroke_line_dashed(0.0, 0.0, 50.0, 0.0, 1.0, [0, 0, 0], &[3.0, 2.0]);
+    let c = page_content(&d);
+    assert_eq!(c.matches("[] 0 d").count(), 2);
+    assert!(!c.contains("[0 0]"));
+    assert!(c.contains("[3 2] 0 d"));
+}
+
+#[test]
+fn negative_and_nan_stroke_widths_become_zero() {
+    let mut d = PdfDoc::new();
+    let p = d.add_page(100.0, 100.0);
+    p.rect_stroke(1.0, 1.0, 10.0, 10.0, -3.0, [0, 0, 0]);
+    p.stroke_line(0.0, 0.0, 5.0, 5.0, f32::NAN, [0, 0, 0]);
+    p.polygon(&[[0.0, 0.0], [5.0, 0.0], [5.0, 5.0]], None, Some(([0, 0, 0], -1.0)));
+    p.circle(20.0, 20.0, 5.0, None, Some(([0, 0, 0], f32::NEG_INFINITY)));
+    let c = page_content(&d);
+    assert_eq!(c.matches("\n0 w ").count(), 4);
+    assert!(!c.contains("-1 w") && !c.contains("-3 w"));
+}
+
+#[test]
+fn non_finite_image_size_stores_nothing() {
+    let mut d = PdfDoc::new();
+    let p = d.add_page(200.0, 200.0);
+    let px = [255u8; 16];
+    for (w, h) in [(f32::NAN, 10.0), (10.0, f32::NAN), (f32::INFINITY, 10.0), (-1.0, 10.0)] {
+        p.image_rgba(0.0, 0.0, w, h, &px, 2, 2);
+    }
+    p.image_rgba(f32::NAN, 0.0, 10.0, 10.0, &px, 2, 2);
+    assert!(p.images.is_empty());
+    assert!(p.content.is_empty());
+}
+
+#[test]
+fn every_draw_method_survives_hostile_numbers() {
+    let bad = [f32::NAN, f32::INFINITY, f32::NEG_INFINITY, -7.0, 0.0, 1.0e30, -1.0e30];
+    let px = [200u8; 16];
+    let mut d = PdfDoc::new();
+    let p = d.add_page(300.0, 300.0);
+    for &a in &bad {
+        for &b in &bad {
+            p.clip_rect(a, b, a, b);
+            p.fill_rect(a, b, b, a, [1, 2, 3]);
+            p.rect_stroke(a, b, a, b, a, [1, 2, 3]);
+            p.stroke_line(a, b, b, a, a, [1, 2, 3]);
+            p.stroke_line_dashed(a, b, b, a, b, [1, 2, 3], &[a, b, 0.0]);
+            p.polyline(&[[a, b], [b, a], [1.0, 1.0]], a, [1, 2, 3], &[b, a]);
+            p.polygon(&[[a, b], [b, a], [1.0, 1.0]], Some([1, 2, 3]), Some(([4, 5, 6], a)));
+            p.circle(a, b, b, Some([1, 2, 3]), Some(([4, 5, 6], a)));
+            p.text(a, b, a, Font::Helvetica, [0, 0, 0], "x");
+            p.text_rotated(a, b, 10.0, Font::TimesRoman, [0, 0, 0], "y", b);
+            p.image_rgba(a, b, b, a, &px, 2, 2);
+        }
+    }
+    p.stroke_line_dashed(0.0, 0.0, 1.0, 1.0, 1.0, [0, 0, 0], &[0.0; 100]);
+    let c = page_content(&d);
+    assert!(!c.contains("NaN") && !c.contains("inf"));
+    let pdf = d.finish();
+    check_xref(&pdf);
+/// Decodes the `<FEFF…>` hex string following `key` in the file bytes.
+fn utf16_entry(pdf: &[u8], key: &str) -> String {
+    let at = find(pdf, key.as_bytes()).unwrap() + key.len();
+    let rest = std::str::from_utf8(&pdf[at..at + 9000.min(pdf.len() - at)]).unwrap_or("");
+    let hex = rest.trim_start().strip_prefix("<FEFF").unwrap();
+    let hex = &hex[..hex.find('>').unwrap()];
+    let units: Vec<u16> = (0..hex.len()).step_by(4).map(|i| u16::from_str_radix(&hex[i..i + 4], 16).unwrap()).collect();
+    String::from_utf16(&units).unwrap()
+}
+
+#[test]
+fn info_strings_with_non_ascii_are_utf16be() {
+    let mut doc = PdfDoc::new();
+    doc.add_page(200.0, 200.0);
+    doc.info.title = "Übersicht €5 – “Q1” 日本 😀".into();
+    doc.info.author = "Müller & Søn".into();
+    let pdf = doc.finish();
+    assert_eq!(utf16_entry(&pdf, "/Title"), "Übersicht €5 – “Q1” 日本 😀");
+    assert_eq!(utf16_entry(&pdf, "/Author"), "Müller & Søn");
+}
+
+#[test]
+fn ascii_info_strings_stay_literal_and_escaped() {
+    let mut doc = PdfDoc::new();
+    doc.add_page(200.0, 200.0);
+    doc.info.title = r"Q1 (draft) a\b".into();
+    let pdf = doc.finish();
+    assert!(find(&pdf, br"/Title (Q1 \(draft\) a\\b)").is_some());
+    assert!(find(&pdf, b"/Producer (GridCraft PDF)").is_some());
+}
+
+#[test]
+fn info_strings_are_capped() {
+    let mut doc = PdfDoc::new();
+    doc.add_page(200.0, 200.0);
+    doc.info.title = "日".repeat(100_000);
+    let pdf = doc.finish();
+    assert_eq!(utf16_entry(&pdf, "/Title").chars().count(), MAX_INFO_CHARS);
+}
diff --git a/crates/ui-egui/src/control.rs b/crates/ui-egui/src/control.rs
index b753b00..d27ea05 100644
--- a/crates/ui-egui/src/control.rs
+++ b/crates/ui-egui/src/control.rs
@@ -242,7 +242,7 @@ pub fn handle(app: &mut SheetApp, ctx: &egui::Context, method: &str, p: &Json) -
                 } else if field == "search" {
                     d.search = s("value").unwrap_or("").to_string();
                 } else {
-                    d.values.insert(field.to_string(), p.get("value").cloned().unwrap_or(Json::Null));
+                    d.set_value(field, p.get("value").cloned().unwrap_or(Json::Null));
                 }
                 ok(json!(d.values))
             }
diff --git a/crates/ui-egui/src/dialogs.rs b/crates/ui-egui/src/dialogs.rs
index 5e859c6..b98a4d5 100644
--- a/crates/ui-egui/src/dialogs.rs
+++ b/crates/ui-egui/src/dialogs.rs
@@ -47,6 +47,17 @@ impl Dialog {
         &self.name
     }
 
+    /// Sets a form value. In Zoom, a Magnification choice is also the percentage `view.zoom` stores.
+    pub(crate) fn set_value(&mut self, key: &str, value: Json) {
+        if self.name == "zoom"
+            && key == "preset"
+            && let Some(p) = value.as_str().and_then(|s| s.parse::<f64>().ok())
+        {
+            self.values.insert("percent".into(), json!(p));
+        }
+        self.values.insert(key.into(), value);
+    }
+
     fn form(name: &str, title: &str, command: &'static str, fields: Vec<Field>, defaults: Json) -> Dialog {
         Dialog {
             name: name.into(),
@@ -370,20 +381,26 @@ impl Dialog {
                 ],
                 json!({"header": "", "footer": "&CPage &P of &N"}),
             ),
-            "pageSetup" => Dialog::form(
-                "pageSetup",
-                "Page Setup",
-                "pageLayout.margins",
-                vec![
-                    Number { key: "left", label: "Left margin (in):" },
-                    Number { key: "right", label: "Right margin (in):" },
-                    Number { key: "top", label: "Top margin (in):" },
-                    Number { key: "bottom", label: "Bottom margin (in):" },
-                    Number { key: "header", label: "Header (in):" },
-                    Number { key: "footer", label: "Footer (in):" },
-                ],
-                json!({"left": 0.7, "right": 0.7, "top": 0.75, "bottom": 0.75, "header": 0.3, "footer": 0.3}),
-            ),
+            "pageSetup" => {
+                // Opens on the active sheet's saved margins, so OK without edits rewrites them unchanged.
+                let m = app.session.active().and_then(|d| d.wb.active()).map(|s| s.print.margins).unwrap_or([0.7, 0.7, 0.75, 0.75, 0.3, 0.3]);
+                // Round off f32 noise so the form shows 0.1, not 0.10000000149.
+                let [left, right, top, bottom, header, footer] = m.map(|v| (f64::from(v) * 1e4).round() / 1e4);
+                Dialog::form(
+                    "pageSetup",
+                    "Page Setup",
+                    "pageLayout.margins",
+                    vec![
+                        Number { key: "left", label: "Left margin (in):" },
+                        Number { key: "right", label: "Right margin (in):" },
+                        Number { key: "top", label: "Top margin (in):" },
+                        Number { key: "bottom", label: "Bottom margin (in):" },
+                        Number { key: "header", label: "Header (in):" },
+                        Number { key: "footer", label: "Footer (in):" },
+                    ],
+                    json!({"left": left, "right": right, "top": top, "bottom": bottom, "header": header, "footer": footer}),
+                )
+            }
             "textToColumns" => Dialog::form(
                 "textToColumns",
                 "Convert Text to Columns",
@@ -415,6 +432,7 @@ impl Dialog {
                     Text { key: "timeline", label: "Timeline range (blank: first column of the selection):" },
                     Text { key: "values", label: "Values range (blank: second column of the selection):" },
                     Text { key: "end", label: "Forecast end (date or number; blank: a third of the history):" },
+                    Text { key: "forecastStart", label: "Forecast start (a date or number in the history; blank: after the last point):" },
                     Check { key: "confidenceInterval", label: "Confidence interval" },
                     Text { key: "confidence", label: "Confidence level (%):" },
                     Text { key: "seasonality", label: "Seasonality (auto, 0 for none, or a season length):" },
@@ -575,7 +593,7 @@ impl Dialog {
                     },
                     Text { key: "errorMessage", label: "Error message:" },
                 ],
-                json!({"type": "list", "operator": "between", "ignoreBlank": true, "dropdown": true, "errorStyle": "stop"}),
+                validation_defaults(app),
             ),
             "cfQuick" => {
                 let ty = p("type").as_str().unwrap_or("cellIs").to_string();
@@ -807,6 +825,36 @@ impl Dialog {
     }
 }
 
+/// Initial values of the Data Validation form: the rule stored on the active cell, so OK without
+/// edits keeps it; a plain list rule when the cell has none.
+fn validation_defaults(app: &SheetApp) -> Json {
+    let mut v = json!({"type": "list", "operator": "between", "ignoreBlank": true, "dropdown": true, "errorStyle": "stop"});
+    let Some(doc) = app.session.active() else { return v };
+    let Some(dv) = doc.wb.active().and_then(|s| s.validations.iter().find(|d| d.ranges.iter().any(|r| r.contains(doc.selection.active)))) else {
+        return v;
+    };
+    // The enums serialize as their variant names; the command takes them in camelCase.
+    let camel = |x: Json| {
+        let name = x.as_str().unwrap_or_default();
+        let mut chars = name.chars();
+        chars.next().map(|c| c.to_lowercase().chain(chars).collect::<String>()).unwrap_or_default()
+    };
+    v["type"] = json!(camel(json!(dv.kind)));
+    v["operator"] = json!(camel(json!(dv.op)));
+    v["errorStyle"] = json!(camel(json!(dv.error_style)));
+    v["formula1"] = json!(dv.f1);
+    if let Some(f2) = &dv.f2 {
+        v["formula2"] = json!(f2);
+    }
+    v["ignoreBlank"] = json!(dv.allow_blank);
+    v["dropdown"] = json!(dv.in_cell_dropdown);
+    v["inputTitle"] = json!(dv.input_title);
+    v["inputMessage"] = json!(dv.input_message);
+    v["errorTitle"] = json!(dv.error_title);
+    v["errorMessage"] = json!(dv.error_message);
+    v
+}
+
 fn abs(r: &gridcraft_engine::core::RangeRef) -> String {
     let a = |c: gridcraft_engine::core::CellRef| format!("${}${}", gridcraft_engine::core::col_to_letters(c.col), c.row + 1);
     if r.is_single() { a(r.start) } else { format!("{}:{}", a(r.start), a(r.end)) }
@@ -891,7 +939,7 @@ pub fn show(app: &mut SheetApp, ctx: &egui::Context) {
         "solver" => 460.0,
         _ => 380.0,
     };
-    let window = egui::Window::new(d.title.clone())
+    let window = egui::Window::new(app.ui.language.tr(&d.title))
         .id(egui::Id::new("dialog").with(&d.name))
         .collapsible(false)
         .resizable(false)
@@ -1223,11 +1271,15 @@ fn paste_special_shortcuts(d: &mut Dialog, ctx: &egui::Context) {
 fn ok_cancel(ui: &mut egui::Ui, confirm: &mut bool, open: &mut bool) {
     ui.add_space(8.0);
     ui.with_layout(egui::Layout::right_to_left(egui::Align::Center), |ui| {
-        let ok = ui.add(egui::Button::new(egui::RichText::new("   OK   ").color(Color32::WHITE)).fill(crate::theme::Tokens::get(ui.ctx()).accent));
+        let lang = crate::i18n::current(ui.ctx());
+        let ok = ui.add(
+            egui::Button::new(egui::RichText::new(format!("   {}   ", lang.tr("OK"))).color(Color32::WHITE))
+                .fill(crate::theme::Tokens::get(ui.ctx()).accent),
+        );
         if ok.clicked() || ui.input(|i| i.key_pressed(Key::Enter)) {
             *confirm = true;
         }
-        if ui.button(" Cancel ").clicked() {
+        if ui.button(format!(" {} ", lang.tr("Cancel"))).clicked() {
             *open = false;
         }
     });
@@ -1288,7 +1340,7 @@ fn form_fields(ui: &mut egui::Ui, d: &mut Dialog) {
                         let cur = d.values.get(key).and_then(Json::as_str).unwrap_or("").to_string();
                         for (val, text) in options {
                             if ui.radio(cur == val, text).clicked() {
-                                d.values.insert(key.into(), json!(val));
+                                d.set_value(key, json!(val));
                             }
                         }
                     });
@@ -1362,9 +1414,20 @@ fn macros(ui: &mut egui::Ui, d: &mut Dialog) {
 }
 
 fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm: &mut bool) {
+    // `d.tab` stays the English name (it is what `open_dialog` and tests pass); only the drawn
+    // labels are translated. The Fill tab is keyed by context: the Alignment tab's "Fill" is a
+    // different word in some languages.
+    let lang = app.ui.language;
     ui.horizontal(|ui| {
-        for tab in ["Number", "Alignment", "Font", "Border", "Fill", "Protection"] {
-            if ui.selectable_label(d.tab == tab, tab).clicked() {
+        for (tab, key) in [
+            ("Number", "Number"),
+            ("Alignment", "Alignment"),
+            ("Font", "Font"),
+            ("Border", "Border"),
+            ("Fill", "Format Cells|Fill"),
+            ("Protection", "Protection"),
+        ] {
+            if ui.selectable_label(d.tab == tab, lang.tr(key)).clicked() {
                 d.tab = tab.to_string();
             }
         }
@@ -1376,20 +1439,20 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
         "Number" => {
             let mut code = st.num_fmt.as_str().to_string();
             ui.columns(2, |cols| {
-                cols[0].label(egui::RichText::new("Category:").strong());
+                cols[0].label(egui::RichText::new(lang.tr("Category:")).strong());
                 for name in
                     ["General", "Number", "Currency", "Accounting", "Short Date", "Long Date", "Time", "Percentage", "Fraction", "Scientific", "Text"]
                 {
                     let c = gridcraft_engine::cmd::format::format_code_for(name).to_string();
-                    if cols[0].selectable_label(code == c, name).clicked() {
+                    if cols[0].selectable_label(code == c, lang.tr(name)).clicked() {
                         code = c;
                     }
                 }
-                cols[1].label(egui::RichText::new("Sample").strong());
+                cols[1].label(egui::RichText::new(lang.tr("Sample")).strong());
                 let preview = app.session.active().map(|doc| gridcraft_engine::display::format(&sample, &code, &doc.wb).text).unwrap_or_default();
                 cols[1].label(egui::RichText::new(preview).font(theme::ui_font(15.0)));
                 cols[1].add_space(8.0);
-                cols[1].label("Type (custom format code):");
+                cols[1].label(lang.tr("Type (custom format code):"));
                 cols[1].text_edit_singleline(&mut code);
                 for c in [
                     "0",
@@ -1418,7 +1481,7 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
         }
         "Alignment" => {
             use gridcraft_engine::model::{HAlign, VAlign};
-            ui.label(egui::RichText::new("Horizontal").strong());
+            ui.label(egui::RichText::new(lang.tr("Horizontal")).strong());
             ui.horizontal_wrapped(|ui| {
                 for (h, n) in [
                     (HAlign::General, "General"),
@@ -1430,10 +1493,10 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
                     (HAlign::CenterAcross, "Center Across Selection"),
                     (HAlign::Distributed, "Distributed"),
                 ] {
-                    ui.radio_value(&mut st.align.h, h, n);
+                    ui.radio_value(&mut st.align.h, h, lang.tr(n));
                 }
             });
-            ui.label(egui::RichText::new("Vertical").strong());
+            ui.label(egui::RichText::new(lang.tr("Vertical")).strong());
             ui.horizontal_wrapped(|ui| {
                 for (v, n) in [
                     (VAlign::Top, "Top"),
@@ -1442,29 +1505,29 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
                     (VAlign::Justify, "Justify"),
                     (VAlign::Distributed, "Distributed"),
                 ] {
-                    ui.radio_value(&mut st.align.v, v, n);
+                    ui.radio_value(&mut st.align.v, v, lang.tr(n));
                 }
             });
             let mut indent = st.align.indent as f32;
-            ui.add(egui::Slider::new(&mut indent, 0.0..=15.0).text("Indent"));
+            ui.add(egui::Slider::new(&mut indent, 0.0..=15.0).text(lang.tr("Indent")));
             st.align.indent = indent as u8;
             let mut rot = if st.align.rotation == 255 { 0.0 } else { st.align.rotation as f32 };
-            ui.add(egui::Slider::new(&mut rot, -90.0..=90.0).text("Orientation (degrees)"));
+            ui.add(egui::Slider::new(&mut rot, -90.0..=90.0).text(lang.tr("Orientation (degrees)")));
             st.align.rotation = rot as i16;
-            ui.checkbox(&mut st.align.wrap, "Wrap text");
-            ui.checkbox(&mut st.align.shrink, "Shrink to fit");
+            ui.checkbox(&mut st.align.wrap, lang.tr("Wrap text"));
+            ui.checkbox(&mut st.align.shrink, lang.tr("Shrink to fit"));
         }
         "Font" => {
-            egui::ComboBox::from_label("Font").selected_text(st.font.name.clone()).show_ui(ui, |ui| {
+            egui::ComboBox::from_label(lang.tr("Font")).selected_text(st.font.name.clone()).show_ui(ui, |ui| {
                 for f in crate::fonts::families() {
                     ui.selectable_value(&mut st.font.name, f.clone(), f.clone());
                 }
             });
-            ui.add(egui::Slider::new(&mut st.font.size, 6.0..=72.0).text("Size"));
+            ui.add(egui::Slider::new(&mut st.font.size, 6.0..=72.0).text(lang.tr("Size")));
             ui.horizontal(|ui| {
-                ui.checkbox(&mut st.font.bold, "Bold");
-                ui.checkbox(&mut st.font.italic, "Italic");
-                ui.checkbox(&mut st.font.strike, "Strikethrough");
+                ui.checkbox(&mut st.font.bold, lang.tr("Bold"));
+                ui.checkbox(&mut st.font.italic, lang.tr("Italic"));
+                ui.checkbox(&mut st.font.strike, lang.tr("Strikethrough"));
             });
             use gridcraft_engine::model::{Underline, VertAlign};
             ui.horizontal(|ui| {
@@ -1475,17 +1538,17 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
                     (Underline::SingleAccounting, "Single Accounting"),
                     (Underline::DoubleAccounting, "Double Accounting"),
                 ] {
-                    ui.radio_value(&mut st.font.underline, u, n);
+                    ui.radio_value(&mut st.font.underline, u, lang.tr(n));
                 }
             });
             ui.horizontal(|ui| {
-                ui.radio_value(&mut st.font.vert, VertAlign::Baseline, "Normal");
-                ui.radio_value(&mut st.font.vert, VertAlign::Superscript, "Superscript");
-                ui.radio_value(&mut st.font.vert, VertAlign::Subscript, "Subscript");
+                ui.radio_value(&mut st.font.vert, VertAlign::Baseline, lang.tr("Normal"));
+                ui.radio_value(&mut st.font.vert, VertAlign::Superscript, lang.tr("Superscript"));
+                ui.radio_value(&mut st.font.vert, VertAlign::Subscript, lang.tr("Subscript"));
             });
-            ui.label("Color:");
+            ui.label(lang.tr("Color:"));
             let colors = app.session.active().map(|doc| doc.wb.theme.colors).unwrap_or_default();
-            if let Some(c) = crate::widgets::color_palette(ui, &colors, "Automatic") {
+            if let Some(c) = crate::widgets::color_palette(ui, &colors, lang.tr("Automatic")) {
                 st.font.color =
                     if c == "none" { gridcraft_engine::model::Color::Auto } else { gridcraft_engine::model::Color::from_hex(&c).unwrap_or_default() };
             }
@@ -1494,10 +1557,10 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
             use gridcraft_engine::model::{BorderLine, BorderStyle};
             let line = BorderLine { style: BorderStyle::Thin, color: gridcraft_engine::model::Color::Auto };
             ui.horizontal(|ui| {
-                if ui.button("None").clicked() {
+                if ui.button(lang.tr("None")).clicked() {
                     st.borders = Default::default();
                 }
-                if ui.button("Outline").clicked() {
+                if ui.button(lang.tr("Outline")).clicked() {
                     st.borders.top = line;
                     st.borders.bottom = line;
                     st.borders.left = line;
@@ -1512,6 +1575,7 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
                 ("Diagonal ↘", &mut st.borders.diag_down),
                 ("Diagonal ↗", &mut st.borders.diag_up),
             ] {
+                let n = lang.tr(n);
                 ui.horizontal(|ui| {
                     ui.label(format!("{n}:"));
                     for (s, label) in [
@@ -1523,6 +1587,7 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
                         (BorderStyle::Dotted, "dotted"),
                         (BorderStyle::Double, "double"),
                     ] {
+                        let label = lang.tr(label);
                         let response = ui.selectable_label(slot.style == s, label);
                         response
                             .widget_info(|| egui::WidgetInfo::labeled(egui::WidgetType::SelectableLabel, ui.is_enabled(), format!("{n} {label}")));
@@ -1537,8 +1602,8 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
         }
         "Fill" => {
             let colors = app.session.active().map(|doc| doc.wb.theme.colors).unwrap_or_default();
-            ui.label("Background Color:");
-            if let Some(c) = crate::widgets::color_palette(ui, &colors, "No Color") {
+            ui.label(lang.tr("Background Color:"));
+            if let Some(c) = crate::widgets::color_palette(ui, &colors, lang.tr("No Color")) {
                 st.fill = if c == "none" {
                     Default::default()
                 } else {
@@ -1547,11 +1612,13 @@ fn format_cells(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, confirm:
             }
         }
         "Protection" => {
-            ui.checkbox(&mut st.protection.locked, "Locked");
-            ui.checkbox(&mut st.protection.hidden, "Hidden");
+            ui.checkbox(&mut st.protection.locked, lang.tr("Locked"));
+            ui.checkbox(&mut st.protection.hidden, lang.tr("Hidden"));
             ui.label(
-                egui::RichText::new("Locking cells or hiding formulas has no effect until you protect the worksheet (Review › Protect Sheet).")
-                    .small(),
+                egui::RichText::new(
+                    lang.tr("Locking cells or hiding formulas has no effect until you protect the worksheet (Review › Protect Sheet)."),
+                )
+                .small(),
             );
         }
         _ => {}
@@ -2352,9 +2419,13 @@ fn solver(ui: &mut egui::Ui, d: &mut Dialog, confirm: &mut bool, open: &mut bool
     let method = text(d, "method");
     ui.horizontal(|ui| {
         ui.label("Select a Solving Method:");
-        let label = |m: &str| if m == "simplex" { "Simplex LP" } else { "GRG Nonlinear" };
+        let label = |m: &str| match m {
+            "simplex" => "Simplex LP",
+            "evolutionary" => "Evolutionary",
+            _ => "GRG Nonlinear",
+        };
         egui::ComboBox::from_id_salt("solverMethod").selected_text(label(&method)).show_ui(ui, |ui| {
-            for m in ["grg", "simplex"] {
+            for m in ["grg", "simplex", "evolutionary"] {
                 if ui.selectable_label(method == m, label(m)).clicked() {
                     d.values.insert("method".into(), json!(m));
                 }
@@ -2362,10 +2433,10 @@ fn solver(ui: &mut egui::Ui, d: &mut Dialog, confirm: &mut bool, open: &mut bool
         });
     });
     ui.label(
-        egui::RichText::new(if method == "simplex" {
-            "Simplex LP: for linear models; integer and binary constraints by branch and bound."
-        } else {
-            "GRG Nonlinear: a local optimum of a smooth model, from the current values."
+        egui::RichText::new(match method.as_str() {
+            "simplex" => "Simplex LP: for linear models; integer and binary constraints by branch and bound.",
+            "evolutionary" => "Evolutionary: a genetic search for models that aren't smooth; every variable cell needs bounds.",
+            _ => "GRG Nonlinear: a local optimum of a smooth model, from the current values.",
         })
         .small(),
     );
@@ -2397,6 +2468,18 @@ fn solver_results(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, open: &
             d.values.insert("restore".into(), json!(true));
         }
     }
+    // Reports describe the solution whether it is kept or not.
+    let solved = d.values.get("values").and_then(Json::as_object).is_some_and(|v| !v.is_empty());
+    if solved {
+        ui.add_space(4.0);
+        ui.label("Reports:");
+        for (key, label) in [("answerReport", "Answer"), ("limitsReport", "Limits")] {
+            let mut on = d.values.get(key).and_then(Json::as_bool).unwrap_or(false);
+            if ui.checkbox(&mut on, label).changed() {
+                d.values.insert(key.into(), json!(on));
+            }
+        }
+    }
     let mut confirm = false;
     ok_cancel(ui, &mut confirm, open);
     if confirm {
@@ -2404,6 +2487,16 @@ fn solver_results(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, open: &
         if changed && restore {
             app.run_or_alert("edit.undo", json!({}));
         }
+        let reports: Vec<&str> = [("answerReport", "answer"), ("limitsReport", "limits")]
+            .into_iter()
+            .filter(|(key, _)| d.values.get(*key).and_then(Json::as_bool) == Some(true))
+            .map(|(_, kind)| kind)
+            .collect();
+        if solved && !reports.is_empty() {
+            let field = |k: &str| d.values.get(k).cloned().unwrap_or(Json::Null);
+            let params = json!({"reports": reports, "model": field("model"), "values": field("values"), "original": field("original"), "message": field("message")});
+            app.run_or_alert("data.solverReport", params);
+        }
         *open = false;
     }
 }
@@ -2460,3 +2553,36 @@ fn spelling(app: &mut SheetApp, ui: &mut egui::Ui, d: &mut Dialog, open: &mut bo
         }
     });
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn data_validation_opens_on_the_rule_of_the_active_cell() {
+        let mut session = gridcraft_engine::Session::default();
+        session.new_workbook();
+        let mut app = SheetApp::new(session, Default::default());
+        app.run("data.validation", json!({"range": "A1", "type": "whole", "operator": "greater", "formula1": "5"})).unwrap();
+        let d = Dialog::open(&mut app, "dataValidation", json!({})).unwrap();
+        assert_eq!(d.values["type"], "whole");
+        assert_eq!(d.values["operator"], "greater");
+        assert_eq!(d.values["formula1"], "5");
+        // OK without edits keeps the rule: 6 is accepted, 4 is rejected.
+        app.run(d.command.unwrap(), build_params(&d)).unwrap();
+        let doc = app.session.active().unwrap();
+        let at = gridcraft_engine::core::CellRef::new(0, 0);
+        assert!(gridcraft_engine::cmd::data::check_validation(&doc.wb, 0, at, "6").is_none());
+        assert!(gridcraft_engine::cmd::data::check_validation(&doc.wb, 0, at, "4").is_some());
+    }
+
+    #[test]
+    fn data_validation_without_a_rule_opens_on_a_blank_list() {
+        let mut session = gridcraft_engine::Session::default();
+        session.new_workbook();
+        let mut app = SheetApp::new(session, Default::default());
+        let d = Dialog::open(&mut app, "dataValidation", json!({})).unwrap();
+        assert_eq!(d.values["type"], "list");
+        assert!(d.values.get("formula1").is_none());
+    }
+}
diff --git a/crates/ui-egui/src/formula_locale.rs b/crates/ui-egui/src/formula_locale.rs
index ad0725e..6e833b9 100644
--- a/crates/ui-egui/src/formula_locale.rs
+++ b/crates/ui-egui/src/formula_locale.rs
@@ -9,6 +9,14 @@ pub(crate) fn canonical(
     sheet: usize,
     cell: gridcraft_engine::core::CellRef,
 ) -> Result<String, ParseError> {
+    // The editor hid the `_xludf.` prefixes of this cell's formula; confirming it unchanged keeps
+    // the user-defined calls instead of binding them to the built-ins of the same name.
+    if let Some(stored) = wb.sheet(sheet).and_then(|sh| sh.cell(cell)).filter(|c| c.formula.is_some()).map(|c| c.input_text())
+        && has_udf_prefix(&stored)
+        && text == display(&stored, locale, wb, sheet)
+    {
+        return Ok(stored);
+    }
     if locale == FormulaLocale::En || wb.sheet(sheet).is_some_and(|sh| wb.styles.get(sh.style_id(cell)).num_fmt.as_str() == "@") {
         return Ok(text.to_string());
     }
@@ -40,16 +48,42 @@ pub(crate) fn canonical(
 }
 
 pub(crate) fn display(text: &str, locale: FormulaLocale, wb: &Workbook, sheet: usize) -> String {
-    // English (and every language without a formula table) shows the stored text untouched,
-    // and skips a parse per frame.
+    // English (and every language without a formula table) shows the stored text, `_xludf.`
+    // prefixes aside, and skips a parse per frame.
     if locale == FormulaLocale::En {
-        return text.to_string();
+        return hide_udf_prefix(text, locale);
     }
     let Some(body) = text.strip_prefix('=') else { return text.to_string() };
-    formula::parse(body)
+    let shown = formula::parse(body)
         .and_then(|expr| formula::print_input(&expr, locale, |name| wb.name(name, sheet).is_some() || wb.table(name).is_some()))
         .map(|body| format!("={body}"))
-        .unwrap_or_else(|_| text.to_string())
+        .unwrap_or_else(|_| text.to_string());
+    hide_udf_prefix(&shown, locale)
+}
+
+const UDF_PREFIX: &str = "_xludf.";
+
+fn has_udf_prefix(text: &str) -> bool {
+    text.to_ascii_lowercase().contains(UDF_PREFIX)
+}
+
+/// Excel shows a user-defined call such as `_xludf.EOMONTH()` as `=EOMONTH()`. Only function
+/// names lose the prefix: text literals and names keep it.
+fn hide_udf_prefix(text: &str, locale: FormulaLocale) -> String {
+    let Some(body) = text.strip_prefix('=').filter(|b| has_udf_prefix(b)) else { return text.to_string() };
+    let Ok(tokens) = formula::lexer::tokenize_locale(body, locale) else { return text.to_string() };
+    let mut out = String::from("=");
+    let mut from = 0;
+    for t in tokens {
+        if matches!(t.tok, formula::lexer::Tok::Func(_))
+            && body.get(t.start..t.start + UDF_PREFIX.len()).is_some_and(|p| p.eq_ignore_ascii_case(UDF_PREFIX))
+        {
+            out.push_str(body.get(from..t.start).unwrap_or(""));
+            from = t.start + UDF_PREFIX.len();
+        }
+    }
+    out.push_str(body.get(from..).unwrap_or(""));
+    out
 }
 
 // Descriptions/signatures for the supported Spanish function table; untranslated functions
diff --git a/crates/ui-egui/src/grid.rs b/crates/ui-egui/src/grid.rs
index d0eef85..a9eb039 100644
--- a/crates/ui-egui/src/grid.rs
+++ b/crates/ui-egui/src/grid.rs
@@ -68,11 +68,15 @@ pub enum Drag {
 pub struct GridState {
     pub drag: Drag,
     pub ensure_visible: bool,
+    /// With `ensure_visible`: scroll to the moving end of the selection instead of the active cell
+    /// (Shift/Ctrl+Shift+arrows keep the active cell on the anchor while the far corner moves).
+    pub reveal_moving_end: bool,
     pub last_title: Option<String>,
     pub drag_select: bool,
     pub rect: Option<Rect>,
     pub cells_rect: Option<Rect>,
-    pub filter_menu: Option<(u32, Pos2)>,
+    /// Column and row of the clicked header cell, and where to open the menu.
+    pub filter_menu: Option<(u32, u32, Pos2)>,
     pub context_menu: Option<Pos2>,
     pub marching_phase: f32,
     /// The selection outline on its way to a new selection.
@@ -84,7 +88,6 @@ pub struct GridState {
     pub last_border: String,
     pub last_fill: String,
     pub last_font_color: String,
-    pub system_clipboard: Option<String>,
     pub trace: Option<serde_json::Value>,
     pub renaming_tab: Option<usize>,
     pub rename_text: String,
@@ -100,6 +103,8 @@ pub struct GridState {
     pub paper: Option<crate::paper_view::PaperCache>,
     /// Header or footer being edited in place (Page Layout view).
     pub hf_edit: Option<crate::paper_view::HfEdit>,
+    /// A page margin being dragged on a ruler (Page Layout view); committed on release.
+    pub ruler_drag: Option<crate::paper_view::RulerDrag>,
     /// Insert › Header & Footer: start editing the first page's header once Page Layout view is up.
     pub hf_start: bool,
     /// The grid geometry of the last frame (hit-testing for agents and tests).
@@ -488,11 +493,17 @@ pub fn show(app: &mut SheetApp, ui: &mut egui::Ui) {
     // Page Layout view: pages on a desk, rulers above and left of the headings.
     let paper = sh.view == gridcraft_engine::model::SheetViewMode::PageLayout;
     let ruler = if paper && !app.session.hide_ruler { crate::paper_view::RULER } else { 0.0 };
-    let grid_rect = Rect::from_min_max(pos2((rect.left() + ruler).min(rect.right()), (rect.top() + ruler).min(rect.bottom())), rect.max);
+    // Right-to-left sheets carry the vertical ruler on the right, beside the row headings.
+    let grid_rect = if rtl {
+        Rect::from_min_max(pos2(rect.left(), (rect.top() + ruler).min(rect.bottom())), pos2((rect.right() - ruler).max(rect.left()), rect.bottom()))
+    } else {
+        Rect::from_min_max(pos2((rect.left() + ruler).min(rect.right()), (rect.top() + ruler).min(rect.bottom())), rect.max)
+    };
     let make_geo = |app: &mut SheetApp, scroll: egui::Vec2| -> Geo {
         if paper {
             let probe = Geo::new(sh, grid_rect, scroll);
             if let Some(g) = crate::paper_view::grid_for(app, &wb, si, sh, probe.cells.size(), scroll) {
+                let g = crate::paper_view::with_dragged_margin(app, &wb, si, g);
                 return Geo::paged(sh, grid_rect, scroll, g);
             }
         }
@@ -533,10 +544,11 @@ pub fn show(app: &mut SheetApp, ui: &mut egui::Ui) {
     view.scroll.x = view.scroll.x.min(max_x);
     view.scroll.y = view.scroll.y.min(max_y);
     let mut geo = make_geo(app, view.scroll);
-    // Keep the active cell visible after keyboard moves.
+    // Keep the active cell (or the moving end of an extension) visible after keyboard moves.
     if app.grid.ensure_visible {
         app.grid.ensure_visible = false;
-        let target = app.editor.as_ref().and_then(|e| e.point_cell).unwrap_or(sel.active);
+        let cell = if std::mem::take(&mut app.grid.reveal_moving_end) { sel.moving_end() } else { sel.active };
+        let target = app.editor.as_ref().and_then(|e| e.point_cell).unwrap_or(cell);
         if paper {
             crate::paper_view::ensure_covers(app, &wb, si, target);
             geo = make_geo(app, view.scroll);
@@ -1373,6 +1385,26 @@ fn range_in_pane(r: RangeRef, rows: (u32, u32), cols: (u32, u32)) -> bool {
     r.start.row <= rows.1 && r.end.row >= rows.0 && r.start.col <= cols.1 && r.end.col >= cols.0
 }
 
+/// The four sides of a `width` wide outline centred on `rect`, cut to `clip` (a little beyond it).
+///
+/// A stroked rectangle that spans a whole column (20 million points tall) loses its precision in
+/// the tessellator and its left and right sides vanish; sides filled from rectangles that stay
+/// near the viewport do not. Sides wholly outside `clip` are left out.
+pub(crate) fn outline_bands(rect: Rect, width: f32, clip: Rect) -> Vec<Rect> {
+    if !rect.is_finite() || !clip.is_finite() {
+        return Vec::new();
+    }
+    let h = width / 2.0;
+    let clip = clip.expand(width * 2.0);
+    let sides = [
+        Rect::from_min_max(pos2(rect.left() - h, rect.top() - h), pos2(rect.left() + h, rect.bottom() + h)),
+        Rect::from_min_max(pos2(rect.right() - h, rect.top() - h), pos2(rect.right() + h, rect.bottom() + h)),
+        Rect::from_min_max(pos2(rect.left() - h, rect.top() - h), pos2(rect.right() + h, rect.top() + h)),
+        Rect::from_min_max(pos2(rect.left() - h, rect.bottom() - h), pos2(rect.right() + h, rect.bottom() + h)),
+    ];
+    sides.into_iter().map(|s| s.intersect(clip)).filter(|s| s.is_finite() && s.width() > 0.0 && s.height() > 0.0).collect()
+}
+
 /// `outline` is where the current area's border is drawn this frame (see `selection_glide`).
 #[allow(clippy::too_many_arguments)]
 pub(crate) fn paint_selection(
@@ -1415,7 +1447,9 @@ pub(crate) fn paint_selection(
         }
     }
     if cur_here {
-        p.rect_stroke(outline.expand(0.5), 0.0, Stroke::new(2.0, t.sel_border), StrokeKind::Middle);
+        for side in outline_bands(outline.expand(0.5), 2.0, p.clip_rect()) {
+            p.rect_filled(side, 0.0, t.sel_border);
+        }
     }
     if active_here && sel.ranges.len() > 1 {
         p.rect_stroke(active, 0.0, Stroke::new(1.0, t.sel_border), StrokeKind::Inside);
@@ -1743,6 +1777,29 @@ fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Response, geo: &
         }
     }
 
+    // Double-click the fill handle: a double-click is also a click, so run it before the handle press returns.
+    if resp.double_clicked()
+        && let Some(p) = pos
+        && on_handle(p)
+    {
+        // Fill down as far as the neighbouring column goes.
+        let src = sel.current();
+        let neighbour = if src.start.col > 0 { src.start.col - 1 } else { src.end.col + 1 };
+        let mut last = src.end.row;
+        while last + 1 < MAX_ROWS && sh.value_ref(CellRef::new(last + 1, neighbour)).is_some_and(|v| !v.is_empty()) && last - src.end.row < 1_000_000
+        {
+            last += 1;
+        }
+        if last > src.end.row {
+            let target = RangeRef::new(src.start, CellRef::new(last, src.end.col));
+            let _ = app.run("edit.autoFill", json!({"source": src.a1(), "target": target.a1()}));
+        }
+        app.grid.drag = Drag::None;
+        app.grid.drag_select = false;
+        resp.request_focus();
+        return;
+    }
+
     // Press: decide the drag mode.
     if resp.drag_started() || (primary_clicked && app.grid.drag == Drag::None) {
         // Where the press began (a drag is only recognised after the pointer has moved).
@@ -1770,6 +1827,9 @@ fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Response, geo: &
                 return;
             }
             let c = geo.col_at(sh, p.x);
+            if point_header(app, wb, sh, RangeRef::cols(c, c)) {
+                return;
+            }
             if resp.drag_started()
                 && !mods.any()
                 && sel.ranges.len() == 1
@@ -1790,6 +1850,9 @@ fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Response, geo: &
                 return;
             }
             let r = geo.row_at(sh, p.y);
+            if point_header(app, wb, sh, RangeRef::rows(r, r)) {
+                return;
+            }
             let range = if mods.shift { RangeRef::rows(sel.anchor.row.min(r), sel.anchor.row.max(r)) } else { RangeRef::rows(r, r) };
             select_ranges(app, range, mods.command, CellRef::new(r, geo.col_at(sh, geo.cells.left() + 1.0)));
             app.grid.drag = Drag::Rows(if mods.shift { sel.anchor.row } else { r });
@@ -1808,7 +1871,7 @@ fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Response, geo: &
         }
         // Filter dropdown buttons.
         if is_filter_button(sh, geo, p) {
-            app.grid.filter_menu = Some((c.col, geo.mirror_pos(p)));
+            app.grid.filter_menu = Some((c.col, c.row, geo.mirror_pos(p)));
             return;
         }
         // Point mode while editing a formula: clicking inserts a reference.
@@ -2046,25 +2109,6 @@ fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Response, geo: &
         app.grid.drag_select = false;
     }
 
-    // Double-click the fill handle.
-    if resp.double_clicked()
-        && let Some(p) = pos
-        && on_handle(p)
-    {
-        // Fill down as far as the neighbouring column goes.
-        let src = sel.current();
-        let neighbour = if src.start.col > 0 { src.start.col - 1 } else { src.end.col + 1 };
-        let mut last = src.end.row;
-        while last + 1 < MAX_ROWS && sh.value_ref(CellRef::new(last + 1, neighbour)).is_some_and(|v| !v.is_empty()) && last - src.end.row < 1_000_000
-        {
-            last += 1;
-        }
-        if last > src.end.row {
-            let target = RangeRef::new(src.start, CellRef::new(last, src.end.col));
-            let _ = app.run("edit.autoFill", json!({"source": src.a1(), "target": target.a1()}));
-        }
-    }
-
     // Right-click: context menu.
     if resp.secondary_clicked()
         && let Some(p) = pos
@@ -2097,6 +2141,16 @@ fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Response, geo: &
     keyboard(app, &ctx, resp, geo, sh);
 }
 
+/// Point mode on a header: inserts the whole-column or whole-row reference instead of selecting.
+fn point_header(app: &mut SheetApp, wb: &Workbook, sh: &Sheet, range: RangeRef) -> bool {
+    let Some(ed) = app.editor.as_mut().filter(|ed| ed.can_point()) else { return false };
+    let r = range.a1();
+    let r = if ed.sheet != wb.active_sheet { format!("{}!{r}", gridcraft_engine::formula::quote_sheet(&sh.name)) } else { r };
+    ed.insert_ref(&r);
+    ed.request_focus = true;
+    true
+}
+
 fn select_to_pointer(app: &mut SheetApp, geo: &Geo, sh: &Sheet, wb: &Workbook, p: Pos2) {
     let cell = CellRef::new(
         geo.row_at(sh, p.y.clamp(geo.cells.top() + 1.0, geo.cells.bottom() - 1.0)),
@@ -2371,6 +2425,7 @@ fn keyboard(app: &mut SheetApp, ctx: &egui::Context, resp: &egui::Response, geo:
                 let mv = |app: &mut SheetApp, dr: i64, dc: i64| {
                     let _ = app.session.run("selection.move", json!({"dr": dr, "dc": dc, "extend": shift, "jump": cmd}));
                     app.grid.ensure_visible = true;
+                    app.grid.reveal_moving_end = shift;
                 };
                 match key {
                     Key::ArrowUp => mv(app, -1, 0),
@@ -2398,6 +2453,12 @@ fn keyboard(app: &mut SheetApp, ctx: &egui::Context, resp: &egui::Response, geo:
                         let _ = app.session.run("selection.set", json!({"cell": CellRef::new(a.row, 0).a1()}));
                         app.grid.ensure_visible = true;
                     }
+                    // Excel: Enter while a copied range is marked pastes it and ends copy mode.
+                    Key::Enter if !m.alt && !m.ctrl && !shift && !cmd && app.session.clipboard.is_some() => {
+                        app.run_or_alert("edit.paste", json!({}));
+                        app.session.clipboard = None;
+                        app.grid.ensure_visible = true;
+                    }
                     Key::Enter => {
                         if m.alt || m.ctrl {
                             app.begin_edit(None, false);
@@ -2480,20 +2541,20 @@ fn popup_dismissed(response: &egui::Response, was_open: bool) -> bool {
     response.ctx.input(|i| !i.focused || i.key_pressed(egui::Key::Escape)) || (was_open && response.clicked_elsewhere())
 }
 
+/// The table whose header cell (`row`, `col`) was clicked, not just the first table in the column.
+fn filter_table_range(sh: &Sheet, col: u32, row: u32) -> Option<RangeRef> {
+    sh.tables.iter().find(|t| t.range.start.row == row && col >= t.range.start.col && col <= t.range.end.col).map(|t| t.range)
+}
+
 fn filter_menu(app: &mut SheetApp, ui: &mut egui::Ui, geo: &Geo, was_open: bool) {
-    let Some((col, at)) = app.grid.filter_menu else { return };
+    let Some((col, row, at)) = app.grid.filter_menu else { return };
     let Some(d) = app.session.active() else { return };
     let wb = d.wb.clone();
     let si = wb.active_sheet;
     let Some(sh) = wb.sheet(si) else { return };
     let _ = geo;
     // Tables get an autofilter on demand.
-    let table_range = sh
-        .tables
-        .iter()
-        .find(|t| t.range.start.row <= at.y as u32 || true)
-        .filter(|t| col >= t.range.start.col && col <= t.range.end.col)
-        .map(|t| t.range);
+    let table_range = filter_table_range(sh, col, row);
     if sh.autofilter.is_none()
         && let Some(r) = table_range
     {
@@ -2547,7 +2608,9 @@ fn filter_menu(app: &mut SheetApp, ui: &mut egui::Ui, geo: &Geo, was_open: bool)
                     c.1 = all_new;
                 }
             }
-            egui::ScrollArea::vertical().max_height(220.0).show(ui, |ui| {
+            // Full width: shrunk to the longest value, the scroll bar sat mid-menu and the wheel only
+            // worked over the values themselves (#432).
+            egui::ScrollArea::vertical().max_height(220.0).auto_shrink([false, true]).show(ui, |ui| {
                 for (v, on) in checks.iter_mut().filter(|(v, _)| matches(v)) {
                     ui.checkbox(on, v.as_str());
                 }
@@ -2651,6 +2714,7 @@ fn context_menu(app: &mut SheetApp, ui: &mut egui::Ui) {
                         "edit.copy" | "edit.cut" => {
                             app.copy_to_clipboard(ui.ctx(), id);
                         }
+                        "edit.paste" => app.paste_from_clipboard(),
                         other => app.run_or_alert(other, json!({})),
                     }
                 }
@@ -2674,7 +2738,17 @@ pub fn point_move(app: &mut SheetApp, ed: &mut EditState, dr: i64, dc: i64, exte
     let from = ed.point_cell.unwrap_or(ed.cell);
     let to = from.offset_clamped(dr, dc);
     let text = if extend {
-        let anchor = ed.point.and_then(|(s, e)| ed.text.get(s..e)).and_then(|t| CellRef::parse(t.split(':').next().unwrap_or(""))).unwrap_or(from);
+        // The anchor is the corner opposite the moving end: the written range is normalized, so
+        // after extending up or left its first cell is the moving end, not the anchor.
+        let pointed = ed.point.and_then(|(s, e)| ed.text.get(s..e)).and_then(RangeRef::parse);
+        let anchor = pointed
+            .map(|r| {
+                CellRef::new(
+                    if from.row == r.start.row { r.end.row } else { r.start.row },
+                    if from.col == r.start.col { r.end.col } else { r.start.col },
+                )
+            })
+            .unwrap_or(from);
         RangeRef::new(anchor, to).a1()
     } else {
         to.a1()
@@ -2715,8 +2789,9 @@ pub(crate) fn paint_overlays(
         p.rect_stroke(r, 2.0, Stroke::new(1.0, Color32::from_gray(160)), StrokeKind::Inside);
         crate::icons::paint(p, r.shrink(3.0), crate::icons::Icon::Chevron, Color32::from_gray(60));
     }
-    // Input message of the active cell's validation.
+    // Input message of the active cell's validation, hidden while its list is open: it would cover the items.
     if app.editor.is_none()
+        && app.grid.list_picker != Some(sel.active)
         && let Some(dv) = sh.validations.iter().find(|d| d.ranges.iter().any(|r| r.contains(sel.active)))
         && dv.show_input
         && !(dv.input_title.is_empty() && dv.input_message.is_empty())
@@ -2893,6 +2968,7 @@ fn header_menu(app: &mut SheetApp, ui: &mut egui::Ui, was_open: bool) {
                         "edit.copy" | "edit.cut" => {
                             app.copy_to_clipboard(ui.ctx(), id);
                         }
+                        "edit.paste" => app.paste_from_clipboard(),
                         other => app.run_or_alert(other, json!({})),
                     }
                 }
@@ -3053,6 +3129,32 @@ mod selection_fill_tests {
 mod tests {
     use super::*;
 
+    #[test]
+    fn filter_menu_uses_the_table_whose_header_was_clicked() {
+        use gridcraft_engine::model::Table;
+        let table = |id: u32, r0: u32, r1: u32| Table {
+            id,
+            name: format!("T{id}"),
+            range: RangeRef::new(CellRef::new(r0, 0), CellRef::new(r1, 0)),
+            header_row: true,
+            totals_row: false,
+            columns: vec![],
+            style: String::new(),
+            banded_rows: true,
+            banded_cols: false,
+            first_col: false,
+            last_col: false,
+            filter_button: true,
+            filter: vec![],
+        };
+        let mut sh = Sheet::new("S");
+        sh.tables.push(table(1, 0, 2));
+        sh.tables.push(table(2, 4, 7));
+        assert_eq!(filter_table_range(&sh, 0, 4), Some(sh.tables[1].range));
+        assert_eq!(filter_table_range(&sh, 0, 0), Some(sh.tables[0].range));
+        assert_eq!(filter_table_range(&sh, 1, 4), None);
+    }
+
     #[test]
     fn cell_text_y_moves_monotonically_in_standard_and_tall_rows() {
         let rect_std = Rect::from_min_max(pos2(0.0, 0.0), pos2(100.0, 20.0));
@@ -3238,3 +3340,27 @@ mod pane_tests {
         assert!(!geo.range_panes(rng(6, 4, 6, 4)).iter().any(|r| r.contains(handle)));
     }
 }
+
+#[cfg(test)]
+mod outline_band_tests {
+    use super::*;
+
+    #[test]
+    fn whole_column_outline_keeps_left_and_right_sides_near_viewport() {
+        let clip = Rect::from_min_max(pos2(0.0, 0.0), pos2(800.0, 600.0));
+        let col = Rect::from_min_max(pos2(100.0, 40.0), pos2(180.0, 20_971_540.0));
+        let sides = outline_bands(col, 2.0, clip);
+        // Left, right and top (in view); the bottom is 20 million points away.
+        assert_eq!(sides.len(), 3);
+        assert!(sides.iter().all(|s| s.bottom() <= clip.bottom() + 4.0 + f32::EPSILON));
+        assert!(sides.iter().any(|s| s.left() < 100.0 && s.right() > 100.0 && s.height() > 500.0));
+        assert!(sides.iter().any(|s| s.left() < 180.0 && s.right() > 180.0 && s.height() > 500.0));
+    }
+
+    #[test]
+    fn outline_outside_the_view_and_non_finite_draw_nothing() {
+        let clip = Rect::from_min_max(pos2(0.0, 0.0), pos2(800.0, 600.0));
+        assert!(outline_bands(Rect::from_min_max(pos2(900.0, 0.0), pos2(950.0, 20.0)), 2.0, clip).is_empty());
+        assert!(outline_bands(Rect::from_min_max(pos2(f32::NAN, 0.0), pos2(1.0, 1.0)), 2.0, clip).is_empty());
+    }
+}
diff --git a/crates/ui-egui/src/i18n.rs b/crates/ui-egui/src/i18n.rs
index 406cc3d..4cc6a3e 100644
--- a/crates/ui-egui/src/i18n.rs
+++ b/crates/ui-egui/src/i18n.rs
@@ -16,6 +16,7 @@ mod fr;
 mod ko;
 mod pt;
 mod ru;
+mod sr;
 mod zh;
 
 #[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
@@ -33,10 +34,11 @@ pub enum Language {
     De,
     Cs,
     Fr,
+    Sr,
 }
 
 impl Language {
-    pub const ALL: [Self; 10] = [Self::En, Self::Es, Self::Zh, Self::Ja, Self::Ko, Self::Ru, Self::PtBr, Self::De, Self::Cs, Self::Fr];
+    pub const ALL: [Self; 11] = [Self::En, Self::Es, Self::Zh, Self::Ja, Self::Ko, Self::Ru, Self::PtBr, Self::De, Self::Cs, Self::Fr, Self::Sr];
 
     /// The language's own name, shown in the switcher.
     pub fn name(self) -> &'static str {
@@ -51,6 +53,7 @@ impl Language {
             Self::De => "Deutsch",
             Self::Cs => "Čeština",
             Self::Fr => "Français",
+            Self::Sr => "Srpski",
         }
     }
 
@@ -67,6 +70,7 @@ impl Language {
             Self::De => "de",
             Self::Cs => "cs",
             Self::Fr => "fr",
+            Self::Sr => "sr",
         }
     }
 
@@ -86,6 +90,7 @@ impl Language {
             "de" => Some(Self::De),
             "cs" => Some(Self::Cs),
             "fr" => Some(Self::Fr),
+            "sr" => Some(Self::Sr),
             _ => None,
         }
     }
@@ -123,6 +128,7 @@ impl Language {
             Self::De => de::translate(text),
             Self::Cs => cs::translate(text),
             Self::Fr => fr::translate(text),
+            Self::Sr => sr::translate(text),
         };
         translated.unwrap_or_else(|| text.rsplit_once('|').map_or(text, |(_, label)| label))
     }
@@ -290,6 +296,12 @@ const JAPANESE: &[(&str, &str)] = &[
     ("Select\nObjects", "オブジェクトの選択"),
     ("Themes", "テーマ"),
     ("Margins", "余白"),
+    ("Left Margin", "左余白"),
+    ("Right Margin", "右余白"),
+    ("Top Margin", "上余白"),
+    ("Bottom Margin", "下余白"),
+    ("Header Margin", "ヘッダーの余白"),
+    ("Footer Margin", "フッターの余白"),
     ("Size", "サイズ"),
     ("Print\nArea", "印刷範囲"),
     ("Set Print Area", "印刷範囲の設定"),
@@ -587,6 +599,7 @@ mod tests {
             assert!(de::translate(english).is_some_and(|text| !text.is_empty()), "missing German: {english}");
             assert!(cs::translate(english).is_some_and(|text| !text.is_empty()), "missing Czech: {english}");
             assert!(fr::translate(english).is_some_and(|text| !text.is_empty()), "missing French: {english}");
+            assert!(sr::translate(english).is_some_and(|text| !text.is_empty()), "missing Serbian: {english}");
         }
         assert_eq!(Language::Ja.tr("Data"), "データ");
         assert_eq!(Language::Zh.tr("Data"), "数据");
@@ -616,6 +629,10 @@ mod tests {
         assert_eq!(Language::Ja.tr("Orientation"), "方向");
         assert_eq!(Language::Cs.tr("Page Layout|Orientation"), "Orientace");
         assert_eq!(Language::Cs.tr("Orientation"), "Orientace textu");
+        assert_eq!(Language::Sr.tr("Data"), "Podaci");
+        assert_eq!(Language::Sr.tr("Sheet1!A1"), "Sheet1!A1");
+        assert_eq!(Language::Sr.tr("Page Layout|Orientation"), "Orijentacija");
+        assert_eq!(Language::Sr.tr("Orientation"), "Orijentacija");
         assert_eq!(Language::parse("xx"), None);
     }
 
@@ -654,6 +671,9 @@ mod tests {
         assert_eq!(Language::from_tag("fr-FR"), Some(Language::Fr));
         assert_eq!(Language::from_tag("fr_CA"), Some(Language::Fr));
         assert_eq!(Language::parse("fr"), Some(Language::Fr));
+        assert_eq!(Language::from_tag("sr-Latn-RS"), Some(Language::Sr));
+        assert_eq!(Language::from_tag("sr-RS"), Some(Language::Sr));
+        assert_eq!(Language::parse("sr"), Some(Language::Sr));
     }
 
     #[test]
diff --git a/crates/ui-egui/src/i18n/cs.rs b/crates/ui-egui/src/i18n/cs.rs
index ca2e559..bf8c35f 100644
--- a/crates/ui-egui/src/i18n/cs.rs
+++ b/crates/ui-egui/src/i18n/cs.rs
@@ -116,6 +116,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "Vybrat\nobjekty",
         "Themes" => "Motivy",
         "Margins" => "Okraje",
+        "Left Margin" => "Levý okraj",
+        "Right Margin" => "Pravý okraj",
+        "Top Margin" => "Horní okraj",
+        "Bottom Margin" => "Dolní okraj",
+        "Header Margin" => "Okraj záhlaví",
+        "Footer Margin" => "Okraj zápatí",
         "Size" => "Velikost",
         "Print\nArea" => "Oblast\ntisku",
         "Set Print Area" => "Nastavit oblast tisku",
@@ -391,6 +397,133 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "More\nFunctions" => "Další\nfunkce",
         "Sheet Options|View" => "Zobrazit",
         "Print" => "Tisknout",
+
+        // Additional runtime labels and tooltips, grouped by source file.
+        // formula_bar.rs (alphabetical keys).
+        "Cancel" => "Zrušit",
+        "Expand formula bar" => "Rozbalit řádek vzorců",
+        "Insert Function" => "Vložit funkci",
+        // grid.rs (alphabetical keys).
+        "Copy" => "Kopírovat",
+        "Cut" => "Vyjmout",
+        "Define Name…" => "Definovat název…",
+        "Delete…" => "Odstranit…",
+        "Filter by Selected Cell's Value" => "Filtrovat podle hodnoty vybrané buňky",
+        "Hide" => "Skrýt",
+        "Insert…" => "Vložit…",
+        "Link…" => "Odkaz…",
+        "New Comment" => "Nový komentář",
+        "Pick From Drop-down List…" => "Vybrat z rozevíracího seznamu…",
+        "Unhide" => "Zobrazit",
+        // ribbon.rs (alphabetical keys).
+        "$ English (United States)" => "$ Angličtina (Spojené státy)",
+        "Add Chart Element" => "Přidat prvek grafu",
+        "Align Left" => "Zarovnat doleva",
+        "Align Right" => "Zarovnat doprava",
+        "Bottom Align" => "Zarovnat dolů",
+        "Calculate Now (F9)" => "Přepočítat (F9)",
+        "Calculate Sheet (⇧F9)" => "Přepočítat list (⇧F9)",
+        "Calculation Options" => "Možnosti výpočtu",
+        "Cell Styles" => "Styly buněk",
+        "Change Chart Type" => "Změnit typ grafu",
+        "Check Accessibility" => "Zkontrolovat přístupnost",
+        "Clear Filter" => "Vymazat filtr",
+        "Column or Bar" => "Sloupcový nebo pruhový graf",
+        "Comments pane" => "Podokno komentářů",
+        "Convert the last ink stroke to a shape" => "Převést poslední tah rukopisu na obrazec",
+        "Convert to Range" => "Převést na oblast",
+        "Custom Sort" => "Vlastní řazení",
+        "Delete Comment" => "Odstranit komentář",
+        "Delete Sheet" => "Odstranit list",
+        "Delete chart" => "Odstranit graf",
+        "Down" => "Dolů",
+        "Edit chart title" => "Upravit název grafu",
+        "Erase ink strokes" => "Vymazat tahy rukopisu",
+        "Every command run in this session (replayable)" => "Všechny příkazy spuštěné v této relaci (lze znovu přehrát)",
+        "Filter (⌘⇧F)" => "Filtr (⌘⇧F)",
+        "Find & Select" => "Najít a vybrat",
+        "Flash Fill (⌘E)" => "Dynamické doplňování (⌘E)",
+        "Forecast Sheet" => "List prognózy",
+        "Format Chart pane" => "Podokno formátu grafu",
+        "Format as Table" => "Formátovat jako tabulku",
+        "Hide Sheet" => "Skrýt list",
+        "Hierarchy & more" => "Hierarchické a další grafy",
+        "Highlighter" => "Zvýrazňovač",
+        "How agents drive GridCraft (MCP / control channel)" => "Jak agenti ovládají GridCraft (MCP / řídicí kanál)",
+        "Import a text or CSV file" => "Importovat textový soubor nebo CSV",
+        "Insert\nSlicer" => "Vložit\nprůřez",
+        "Insert Function (⇧F3)" => "Vložit funkci (⇧F3)",
+        "Insert Link (⌘K)" => "Vložit odkaz (⌘K)",
+        "Insert Sheet" => "Vložit list",
+        "Insert Slicer" => "Vložit průřez",
+        "Insert a picture" => "Vložit obrázek",
+        "Insert a slicer to filter a table" => "Vložit průřez pro filtrování tabulky",
+        "Insert an icon" => "Vložit ikonu",
+        "Line or Area" => "Spojnicový nebo plošný graf",
+        "Macros" => "Makra",
+        "Macros and scripts in this workbook (Alt+F8)" => "Makra a skripty v tomto sešitu (Alt+F8)",
+        "Middle Align" => "Zarovnat doprostřed",
+        "More commands" => "Další příkazy",
+        "Move or Copy Sheet…" => "Přesunout nebo zkopírovat list…",
+        "Name Manager" => "Správce názvů",
+        "Page Breaks" => "Konce stránek",
+        "Paper Size" => "Velikost papíru",
+        "Paste (⌘V)" => "Vložit (⌘V)",
+        "Pen\nBlack" => "Pero\nčerné",
+        "Pen\nBlue" => "Pero\nmodré",
+        "Pen\nRed" => "Pero\nčervené",
+        "Pie or Doughnut" => "Výsečový nebo prstencový graf",
+        "Print Area" => "Oblast tisku",
+        "Print Titles" => "Tisk názvů",
+        "Protect\nSheet" => "Zamknout\nlist",
+        "Protect Sheet" => "Zamknout list",
+        "Protect Workbook structure" => "Zamknout strukturu sešitu",
+        "Recommended Charts" => "Doporučené grafy",
+        "Redo (⌘Y)" => "Znovu (⌘Y)",
+        "Remove Duplicates" => "Odebrat duplicity",
+        "Rename Sheet" => "Přejmenovat list",
+        "Save (⌘S)" => "Uložit (⌘S)",
+        "Scatter or Bubble" => "Bodový nebo bublinový graf",
+        "Search and run any command" => "Vyhledat a spustit libovolný příkaz",
+        "Search commands (⌘⇧Space)" => "Vyhledat příkazy (⌘⇧Space)",
+        "Select Data" => "Vybrat data",
+        "Select and move ink and shapes" => "Vybrat a přesunout rukopis a obrazce",
+        "Series…" => "Řady…",
+        "Share: export or save a copy" => "Sdílet: exportovat nebo uložit kopii",
+        "Show Formulas (⌃`)" => "Zobrazit vzorce (⌃`)",
+        "Slicer" => "Průřez",
+        "Sort & Filter" => "Seřadit a filtrovat",
+        "Spelling (F7)" => "Pravopis (F7)",
+        "Statistic" => "Statistické grafy",
+        "Switch Row/Column" => "Prohodit řádky/sloupce",
+        "Table (⌘T)" => "Tabulka (⌘T)",
+        "Table Styles" => "Styly tabulky",
+        "Text Box" => "Textové pole",
+        "Text to Columns" => "Text do sloupců",
+        "Top Align" => "Zarovnat nahoru",
+        "Undo (⌘Z)" => "Zpět (⌘Z)",
+        "Undo list" => "Seznam akcí k vrácení",
+        "Unhide Sheet…" => "Zobrazit list…",
+        "Up" => "Nahoru",
+        "Version, contributors and the AI models that helped" => "Verze, přispěvatelé a modely AI, které pomáhaly",
+        "Watch\nWindow" => "Okno\nsledování",
+        "What-If Analysis" => "Citlivostní analýza",
+        "Workbook\nStatistics" => "Statistika\nsešitu",
+        "Workbook Statistics" => "Statistika sešitu",
+        "Zoom to 100%" => "Přiblížit na 100 %",
+        "Zoom to Selection" => "Přiblížit na výběr",
+        "Zoom…" => "Lupa…",
+        "£ English (United Kingdom)" => "£ Angličtina (Spojené království)",
+        "¥ Japanese" => "¥ Japonština",
+        "€ Euro" => "€ Euro",
+        // tabs.rs (alphabetical keys).
+        "New sheet (⇧F11)" => "Nový list (⇧F11)",
+        "Next sheet" => "Další list",
+        "Previous sheet" => "Předchozí list",
+        "Zoom In" => "Přiblížit",
+        "Zoom Out" => "Oddálit",
+        // widgets.rs (alphabetical keys).
+        "Dismiss" => "Zavřít",
         _ => return None,
     })
 }
diff --git a/crates/ui-egui/src/i18n/de.rs b/crates/ui-egui/src/i18n/de.rs
index 2ad37f6..75653e5 100644
--- a/crates/ui-egui/src/i18n/de.rs
+++ b/crates/ui-egui/src/i18n/de.rs
@@ -116,6 +116,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "Objekte\nauswählen",
         "Themes" => "Designs",
         "Margins" => "Seitenränder",
+        "Left Margin" => "Linker Seitenrand",
+        "Right Margin" => "Rechter Seitenrand",
+        "Top Margin" => "Oberer Seitenrand",
+        "Bottom Margin" => "Unterer Seitenrand",
+        "Header Margin" => "Kopfzeilenabstand",
+        "Footer Margin" => "Fußzeilenabstand",
         "Size" => "Größe",
         "Print\nArea" => "Druck-\nbereich",
         "Set Print Area" => "Druckbereich festlegen",
diff --git a/crates/ui-egui/src/i18n/es.rs b/crates/ui-egui/src/i18n/es.rs
index da41bd7..0582110 100644
--- a/crates/ui-egui/src/i18n/es.rs
+++ b/crates/ui-egui/src/i18n/es.rs
@@ -117,6 +117,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "Seleccionar\nobjetos",
         "Themes" => "Temas",
         "Margins" => "Márgenes",
+        "Left Margin" => "Margen izquierdo",
+        "Right Margin" => "Margen derecho",
+        "Top Margin" => "Margen superior",
+        "Bottom Margin" => "Margen inferior",
+        "Header Margin" => "Margen del encabezado",
+        "Footer Margin" => "Margen del pie de página",
         "Size" => "Tamaño",
         "Print\nArea" => "Área de\nimpresión",
         "Set Print Area" => "Establecer área de impresión",
diff --git a/crates/ui-egui/src/i18n/fr.rs b/crates/ui-egui/src/i18n/fr.rs
index 7bf9fd1..c70b25c 100644
--- a/crates/ui-egui/src/i18n/fr.rs
+++ b/crates/ui-egui/src/i18n/fr.rs
@@ -11,32 +11,32 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Transpose" => "Transposer",
         "Paste Link" => "Coller la liaison",
         "Paste Special…" => "Collage spécial…",
-        "Insert Copied Cells" => "Insérer les cellules coupées",
-        "Insert Copied Cells…" => "Coller en insérant",
-        "Insert Cut Cells" => "Insérer des cases à cocher dans les cellules sélectionnées",
-        "Insert Paste" => "Taille de l’interface",
+        "Insert Copied Cells" => "Insérer les cellules copiées",
+        "Insert Copied Cells…" => "Insérer les cellules copiées…",
+        "Insert Cut Cells" => "Insérer les cellules coupées",
+        "Insert Paste" => "Insérer en collant",
         "Cut (⌘X)" => "Couper (⌘X)",
         "Copy (⌘C)" => "Copier (⌘C)",
         "Format Painter (double-click to keep it on)" => "Reproduire la mise en forme (double-clic pour la conserver)",
         "Bold (⌘B)" => "Gras (⌘B)",
         "Italic (⌘I)" => "Italique (⌘I)",
         "Underline (⌘U)" => "Souligné (⌘U)",
-        "Double Underline" => "Double souligné",
+        "Double Underline" => "Double soulignement",
         "Strikethrough" => "Barré",
         "Underline" => "Souligné",
-        "Increase Font Size" => "Augmenter la taille de la police",
-        "Decrease Font Size" => "Réduire la taille de la police",
-        "Wrap Text" => "Renvoyer à la ligne",
+        "Increase Font Size" => "Augmenter la taille de police",
+        "Decrease Font Size" => "Réduire la taille de police",
+        "Wrap Text" => "Renvoyer à la ligne automatiquement",
         "Merge & Center" => "Fusionner et centrer",
         "Merge Cells" => "Fusionner les cellules",
         "Merge Across" => "Fusionner horizontalement",
-        "Unmerge Cells" => "Dissocier les cellules",
+        "Unmerge Cells" => "Annuler la fusion des cellules",
         "Fill Color" => "Couleur de remplissage",
         "Font Color" => "Couleur de police",
         "Borders" => "Bordures",
-        "Top\nAlign" => "Aligner en haut",
-        "Middle\nAlign" => "Aligner au centre",
-        "Bottom\nAlign" => "Aligner en bas",
+        "Top\nAlign" => "Aligner en\nhaut",
+        "Middle\nAlign" => "Aligner au\nmilieu",
+        "Bottom\nAlign" => "Aligner en\nbas",
         "Left" => "Gauche",
         "Right" => "Droite",
         "Center" => "Centré",
@@ -52,17 +52,17 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Rotate Text Down" => "Pivoter le texte vers le bas",
         "Accounting Number Format" => "Format de nombre Comptabilité",
         "Percent Style" => "Style de pourcentage",
-        "Comma Style" => "Style de virgule",
+        "Comma Style" => "Style de milliers",
         "Increase Decimal" => "Ajouter une décimale",
         "Decrease Decimal" => "Retirer une décimale",
         "More Accounting Formats…" => "Autres formats comptables…",
-        "Conditional\nFormatting" => "Mise en forme conditionnelle",
+        "Conditional\nFormatting" => "Mise en forme\nconditionnelle",
         "Conditional Formatting" => "Mise en forme conditionnelle",
-        "Format\nas Table" => "Mettre sous forme de tableau",
-        "Cell\nStyles" => "Styles de cellules",
+        "Format\nas Table" => "Mettre sous forme\nde tableau",
+        "Cell\nStyles" => "Styles de\ncellules",
         "Format Cells…" => "Format de cellules…",
-        "Format Cell Alignment…" => "Format d’alignement de cellule…",
-        "Format\nPane" => "Volet Format",
+        "Format Cell Alignment…" => "Format d'alignement de cellule…",
+        "Format\nPane" => "Volet\nFormat",
         "Format" => "Format",
         "Insert" => "Insertion",
         "Insert Cells…" => "Insérer des cellules…",
@@ -90,58 +90,64 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Clear Hyperlinks" => "Effacer les liens hypertexte",
         "AutoSum" => "Somme automatique",
         "AutoSum (⌘⇧T)" => "Somme automatique (⌘⇧T)",
-        "Flash\nFill" => "Remplissage instantané",
+        "Flash\nFill" => "Remplissage\ninstantané",
         "Flash Fill" => "Remplissage instantané",
         "Fill" => "Remplir",
-        "Clear Print Area" => "Effacer la zone d’impression",
-        "Find &\nSelect" => "Rechercher et sélectionner",
+        "Clear Print Area" => "Effacer la zone d'impression",
+        "Find &\nSelect" => "Rechercher et\nsélectionner",
         "Find…" => "Rechercher…",
         "Replace…" => "Remplacer…",
         "Go To…" => "Atteindre…",
         "Go To Special…" => "Atteindre spécial…",
         "PivotTable" => "Tableau croisé dynamique",
-        "Recommended\nCharts" => "Graphiques recommandés",
+        "Recommended\nCharts" => "Graphiques\nrecommandés",
         "Table" => "Tableau",
         "Pictures" => "Images",
         "Shapes" => "Formes",
         "Icons" => "Icônes",
-        "Text\nBox" => "Zone de texte",
+        "Text\nBox" => "Zone de\ntexte",
         "Comment" => "Commentaire",
-        "New\nComment" => "Nouveau commentaire",
+        "New\nComment" => "Nouveau\ncommentaire",
         "New Note" => "Nouvelle note",
         "Show/Hide Note" => "Afficher/masquer la note",
-        "Header &\nFooter" => "En-tête et pied de page",
-        "Text to\nColumns" => "Convertir",
+        "Header &\nFooter" => "En-tête et\npied de page",
+        "Text to\nColumns" => "Convertir le texte\nen colonnes",
         "Link" => "Lien",
         "Symbol" => "Symbole",
-        "Sparklines" => "Sparklines",
-        "Checkbox" => "Cliquez pour ajouter des données",
-        "Insert checkboxes in the selected cells" => "Mots-clés",
+        "Sparklines" => "Courbes de tendance",
+        "Checkbox" => "Case à cocher",
+        "Insert checkboxes in the selected cells" => "Insérer des cases à cocher dans les cellules sélectionnées",
         "Header & Footer" => "En-tête et pied de page",
-        "Draw with ink" => "Dessiner avec l’encre",
+        "Draw with ink" => "Dessiner à l'encre",
         "Eraser" => "Gomme",
-        "Ink to\nShape" => "Encre vers forme",
-        "Select\nObjects" => "Sélection d’objets",
+        "Ink to\nShape" => "Encre en\nforme",
+        "Select\nObjects" => "Sélectionner les\nobjets",
         "Themes" => "Thèmes",
         "Margins" => "Marges",
+        "Left Margin" => "Marge gauche",
+        "Right Margin" => "Marge droite",
+        "Top Margin" => "Marge haute",
+        "Bottom Margin" => "Marge basse",
+        "Header Margin" => "Marge de l'en-tête",
+        "Footer Margin" => "Marge du pied de page",
         "Size" => "Taille",
-        "Print\nArea" => "Zone d’impression",
-        "Set Print Area" => "Définir la zone d’impression",
+        "Print\nArea" => "Zone\nd'impression",
+        "Set Print Area" => "Définir la zone d'impression",
         "Breaks" => "Sauts",
         "Insert Page Break" => "Insérer un saut de page",
         "Remove Page Break" => "Supprimer le saut de page",
         "Reset All Page Breaks" => "Réinitialiser tous les sauts de page",
-        "Print\nTitles" => "Titres à imprimer",
-        "Sheet\nRight-to-Left" => "Afficher la barre de formule",
-        "Sheet Right-to-Left" => "Feuilles",
-        "Narrow" => "Étroites",
-        "Wide" => "Larges",
-        "Normal" => "Normales",
+        "Print\nTitles" => "Titres à\nimprimer",
+        "Sheet\nRight-to-Left" => "Feuille de\ndroite à gauche",
+        "Sheet Right-to-Left" => "Feuille de droite à gauche",
+        "Narrow" => "Étroit",
+        "Wide" => "Large",
+        "Normal" => "Normal",
         "Portrait" => "Portrait",
         "Landscape" => "Paysage",
         "Custom Margins…" => "Marges personnalisées…",
-        "Insert\nFunction" => "Insérer une fonction",
-        "Name\nManager" => "Gestionnaire de noms",
+        "Insert\nFunction" => "Insérer une\nfonction",
+        "Name\nManager" => "Gestionnaire\nde noms",
         "Define Name" => "Définir un nom",
         "Use in Formula" => "Utiliser dans la formule",
         "Create from Selection" => "Créer à partir de la sélection",
@@ -152,90 +158,92 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Error Checking" => "Vérification des erreurs",
         "Evaluate Formula" => "Évaluation de formule",
         "Watch Window" => "Fenêtre Espion",
-        "Calculation\nOptions" => "Options de calcul",
+        "Calculation\nOptions" => "Options de\ncalcul",
         "Calculate Now" => "Calculer maintenant",
         "Calculate Sheet" => "Calculer la feuille",
         "Automatic" => "Automatique",
         "Automatic Except for Data Tables" => "Automatique sauf pour les tables de données",
         "Manual" => "Manuel",
-        "Sort &\nFilter" => "Trier et filtrer",
+        "Sort &\nFilter" => "Trier et\nfiltrer",
         "Sort" => "Trier",
         "Sort A to Z" => "Trier de A à Z",
         "Sort Z to A" => "Trier de Z à A",
         "Custom Sort…" => "Tri personnalisé…",
         "Filter" => "Filtrer",
         "Reapply" => "Réappliquer",
-        "Get Data\n(Text/CSV)" => "Obtenir des données (Texte/CSV)",
-        "Remove\nDuplicates" => "Supprimer les doublons",
-        "Data\nValidation" => "Validation des données",
+        "Get Data\n(Text/CSV)" => "Obtenir des données\n(Texte/CSV)",
+        "Remove\nDuplicates" => "Supprimer les\ndoublons",
+        "Data\nValidation" => "Validation des\ndonnées",
         "Data Validation" => "Validation des données",
         "Data Validation…" => "Validation des données…",
         "Circle Invalid Data" => "Cerner les données non valides",
         "Clear Validation" => "Effacer la validation",
         "Group" => "Grouper",
         "Ungroup" => "Dissocier",
-        "Show Detail" => "Titre",
-        "Hide Detail" => "Insérer les cellules copiées",
+        "Show Detail" => "Afficher le détail",
+        "Hide Detail" => "Masquer le détail",
         "Subtotal" => "Sous-total",
-        "Data\nAnalysis" => "Description",
-        "Data Analysis" => "Analyse\nde données",
-        "Solver" => "Page web (.html)",
-        "What-If\nAnalysis" => "Analyse scénarios",
+        "Data\nAnalysis" => "Analyse de\ndonnées",
+        "Data Analysis" => "Analyse de données",
+        "Solver" => "Solveur",
+        "What-If\nAnalysis" => "Analyse\nde scénarios",
         "Data Table…" => "Table de données…",
         "Scenario Manager…" => "Gestionnaire de scénarios…",
         "Goal Seek…" => "Valeur cible…",
-        "Forecast\nSheet" => "Aller au pied de page",
+        "Forecast\nSheet" => "Feuille de\nprévision",
         "Spelling" => "Orthographe",
-        "Check\nAccessibility" => "Vérifier l’accessibilité",
-        "Threaded Comments" => "Commentaires threadés",
-        "Show\nComments" => "Afficher les commentaires",
-        "Previous" => "Imprimer les feuilles actives",
-        "Next" => "Aucun classeur récent pour le moment.",
-        "Previous Comment" => "Imprimer tout le classeur",
-        "Next Comment" => "Aucun classeur n’est ouvert.",
-        "Show All Notes" => "Objet",
-        "Convert to Comments" => "Créer un PDF",
-        "Protect\nWorkbook" => "Protéger le classeur",
-        "Allow Edit\nRanges" => "Animations",
-        "Allow Edit Ranges" => "Autoriser la\nmodification des plages",
-        "Unprotect\nSheet" => "Ôter la protection de la feuille",
+        "Check\nAccessibility" => "Vérifier\nl'accessibilité",
+        "Threaded Comments" => "Commentaires en fil de discussion",
+        "Show\nComments" => "Afficher les\ncommentaires",
+        "Previous" => "Précédent",
+        "Next" => "Suivant",
+        "Previous Comment" => "Commentaire précédent",
+        "Next Comment" => "Commentaire suivant",
+        "Show All Notes" => "Afficher toutes les notes",
+        "Convert to Comments" => "Convertir en commentaires",
+        "Protect\nWorkbook" => "Protéger le\nclasseur",
+        "Allow Edit\nRanges" => "Autoriser la modification\ndes plages",
+        "Allow Edit Ranges" => "Autoriser la modification des plages",
+        "Unprotect\nSheet" => "Ôter la protection\nde la feuille",
         "Protect Sheet…" => "Protéger la feuille…",
         "Comments" => "Commentaires",
         "Notes" => "Notes",
-        "Page Break\nPreview" => "Aperçu des sauts de page",
-        "Page\nLayout" => "Mise en page",
+        "Page Break\nPreview" => "Aperçu des sauts\nde page",
+        "Page\nLayout" => "Mise en\npage",
         "Formula Bar" => "Barre de formule",
         "Gridlines" => "Quadrillage",
         "Headings" => "En-têtes",
         "Zoom" => "Zoom",
-        "100%" => "100%",
-        "Zoom to\nSelection" => "Zoom sur la sélection",
-        "Freeze\nPanes" => "Figer les volets",
+        "100%" => "100 %",
+        "Zoom to\nSelection" => "Zoom sur la\nsélection",
+        "Freeze\nPanes" => "Figer les\nvolets",
         "Freeze Panes" => "Figer les volets",
         "Freeze Top Row" => "Figer la ligne supérieure",
         "Freeze First Column" => "Figer la première colonne",
         "Unfreeze Panes" => "Libérer les volets",
         "Dark Mode" => "Mode sombre",
-        "Display theme" => "Thème d’affichage",
-        "Animations" => "Auteur",
-        "Glide the selection outline to the cell you move to instead of jumping there" => "Aller à l’en-tête",
+        "Display theme" => "Thème d'affichage",
+        "Animations" => "Animations",
+        "Glide the selection outline to the cell you move to instead of jumping there" => {
+            "Faire glisser le contour de la sélection jusqu'à la cellule de destination au lieu d'y sauter directement"
+        }
         "System" => "Système",
         "Light" => "Clair",
         "Dark" => "Sombre",
-        "Interface language" => "Langue de l’interface",
-        "Interface size" => "Emplacement",
-        "Auto" => "Retour",
-        "Drag to freeze columns" => "Faites glisser pour figer les lignes",
-        "Drag to freeze rows" => "Activer le calcul itératif",
-        "Command\nPalette" => "Palette de commandes",
-        "Agent\nControl" => "Contrôle de l’agent",
-        "Action\nJournal" => "Journal des actions",
-        "About\nGridCraft" => "À propos de GridCraft",
+        "Interface language" => "Langue de l'interface",
+        "Interface size" => "Taille de l'interface",
+        "Auto" => "Automatique",
+        "Drag to freeze columns" => "Faites glisser pour figer les colonnes",
+        "Drag to freeze rows" => "Faites glisser pour figer les lignes",
+        "Command\nPalette" => "Palette de\ncommandes",
+        "Agent\nControl" => "Contrôle de\nl'agent",
+        "Action\nJournal" => "Journal des\nactions",
+        "About\nGridCraft" => "À propos de\nGridCraft",
         "Share" => "Partager",
-        "Add Chart\nElement" => "Ajouter un élément de graphique",
-        "Change\nChart Type" => "Modifier le type de graphique",
-        "Switch\nRow/Column" => "Permuter ligne/colonne",
-        "Select\nData" => "Nom de la\nfeuille",
+        "Add Chart\nElement" => "Ajouter un élément\nde graphique",
+        "Change\nChart Type" => "Modifier le type\nde graphique",
+        "Switch\nRow/Column" => "Permuter\nligne/colonne",
+        "Select\nData" => "Sélectionner les\ndonnées",
         "Data Labels: None" => "Étiquettes de données : Aucune",
         "Data Labels: Show" => "Étiquettes de données : Afficher",
         "Legend: None" => "Légende : Aucune",
@@ -244,10 +252,10 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Legend: Right" => "Légende : Droite",
         "Gridlines: None" => "Quadrillage : Aucun",
         "Gridlines: Show" => "Quadrillage : Afficher",
-        "Chart\nTitle" => "Titre du graphique",
-        "Delete\nChart" => "Supprimer le graphique",
-        "Convert\nto Range" => "Convertir en plage",
-        "Table\nStyles" => "Styles de tableau",
+        "Chart\nTitle" => "Titre du\ngraphique",
+        "Delete\nChart" => "Supprimer le\ngraphique",
+        "Convert\nto Range" => "Convertir\nen plage",
+        "Table\nStyles" => "Styles de\ntableau",
         "Top 10 Items" => "10 premiers éléments",
         "Top 10%" => "10 % les plus élevés",
         "Bottom 10 Items" => "10 derniers éléments",
@@ -259,7 +267,7 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Constants" => "Constantes",
         "Data Bars" => "Barres de données",
         "Color Scales" => "Échelles de couleurs",
-        "Icon Sets" => "Jeux d’icônes",
+        "Icon Sets" => "Jeux d'icônes",
         "Home" => "Accueil",
         "Draw" => "Dessin",
         "Page Layout" => "Mise en page",
@@ -293,96 +301,104 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "More Number Formats…" => "Autres formats numériques…",
         "Financial" => "Financières",
         "Logical" => "Logiques",
-        "Date &\nTime" => "Date et heure",
-        "Lookup &\nReference" => "Recherche et référence",
-        "Math &\nTrig" => "Maths et trigonométrie",
-        "More\nFunctions" => "Autres fonctions",
-        "Sheet Options|View" => "Affichage",
+        "Date &\nTime" => "Date et\nheure",
+        "Lookup &\nReference" => "Recherche et\nréférence",
+        "Math &\nTrig" => "Maths et\ntrigonométrie",
+        "More\nFunctions" => "Autres\nfonctions",
+        "Sheet Options|View" => "Options de la feuille|Affichage",
         "Print" => "Impression",
-        "Click to add data" => "Fermer",
-        "Add header" => "Autoriser la modification des plages",
-        "Add footer" => "Ajouter un en-tête",
+        "Click to add data" => "Cliquez pour ajouter des données",
+        "Add header" => "Ajouter un en-tête",
+        "Add footer" => "Ajouter un pied de page",
         "(none)" => "(aucun)",
-        "Header" => "Informations",
-        "Footer" => "Feuille de\nprévision",
-        "Page\nNumber" => "Page précédente",
-        "Number\nof Pages" => "Général",
-        "Current\nDate" => "Heure\nactuelle",
-        "Current\nTime" => "Analyse de données",
-        "File\nPath" => "Ajuster la feuille sur une seule page",
-        "File\nName" => "Chemin\ndu fichier",
-        "Sheet\nName" => "Afficher le détail",
-        "Go to\nHeader" => "Masquer le détail",
-        "Go to\nFooter" => "En-tête",
-        "Page Number" => "Numéro\nde page",
-        "Number of Pages" => "Options",
-        "Current Date" => "Heure actuelle",
-        "Current Time" => "Date\nactuelle",
-        "File Path" => "Nom du\nfichier",
-        "File Name" => "Chemin du fichier",
-        "Sheet Name" => "Feuille de\ndroite à gauche",
-        "Go to Header" => "Aller à\nl’en-tête",
-        "Go to Footer" => "Aller au\npied de page",
-        "Ruler" => "Enregistrer sous",
-        "File" => "Nom du fichier",
-        "Back" => "Classeur vide",
-        "New" => "Page suivante",
-        "Open" => "Enregistrement",
-        "Info" => "Insérer les cellules copiées…",
-        "Save" => "Type de fichier",
-        "Save As" => "Enregistrer la feuille sous forme de document PDF en conservant sa mise en page.",
-        "Export" => "Fichier",
-        "Close" => "Société",
-        "Options" => "PDF (*.pdf)",
-        "Blank workbook" => "Parcourir…",
-        "Recent" => "Enregistrer automatiquement les classeurs .xlsx après chaque modification",
-        "No recent workbooks yet." => "Rien à imprimer.",
-        "More workbooks" => "Commentaire suivant",
-        "Browse…" => "CSV (séparé par des virgules)",
-        "Not saved yet" => "Nombre\nde pages",
-        "Location" => "Nouveau",
-        "Sheets" => "Solveur",
-        "Protect Workbook" => "Enregistrer",
-        "Sheet structure is locked: sheets can't be added, moved, renamed or deleted." => "Afficher toutes les notes",
-        "Lock the sheet structure so sheets can't be added, moved, renamed or deleted." => "Suivant",
-        "Properties" => "Règle",
+        "Header" => "En-tête",
+        "Footer" => "Pied de page",
+        "Page\nNumber" => "Numéro de\npage",
+        "Number\nof Pages" => "Nombre\nde pages",
+        "Current\nDate" => "Date\nactuelle",
+        "Current\nTime" => "Heure\nactuelle",
+        "File\nPath" => "Chemin\ndu fichier",
+        "File\nName" => "Nom du\nfichier",
+        "Sheet\nName" => "Nom de la\nfeuille",
+        "Go to\nHeader" => "Aller à\nl'en-tête",
+        "Go to\nFooter" => "Aller au\npied de page",
+        "Page Number" => "Numéro de page",
+        "Number of Pages" => "Nombre de pages",
+        "Current Date" => "Date actuelle",
+        "Current Time" => "Heure actuelle",
+        "File Path" => "Chemin du fichier",
+        "File Name" => "Nom du fichier",
+        "Sheet Name" => "Nom de la feuille",
+        "Go to Header" => "Aller à l'en-tête",
+        "Go to Footer" => "Aller au pied de page",
+        "Ruler" => "Règle",
+        "File" => "Fichier",
+        "Back" => "Retour",
+        "New" => "Nouveau",
+        "Open" => "Ouvrir",
+        "Info" => "Informations",
+        "Save" => "Enregistrer",
+        "Save As" => "Enregistrer sous",
+        "Export" => "Exporter",
+        "Close" => "Fermer",
+        "Options" => "Options",
+        "Blank workbook" => "Classeur vide",
+        "Recent" => "Récent",
+        "No recent workbooks yet." => "Aucun classeur récent pour le moment.",
+        "More workbooks" => "Plus de classeurs",
+        "Browse…" => "Parcourir…",
+        "Not saved yet" => "Pas encore enregistré",
+        "Location" => "Emplacement",
+        "Sheets" => "Feuilles",
+        "Protect Workbook" => "Protéger le classeur",
+        "Sheet structure is locked: sheets can't be added, moved, renamed or deleted." => {
+            "La structure de la feuille est verrouillée : les feuilles ne peuvent pas être ajoutées, déplacées, renommées ou supprimées."
+        }
+        "Lock the sheet structure so sheets can't be added, moved, renamed or deleted." => {
+            "Verrouiller la structure des feuilles pour qu'elles ne puissent pas être ajoutées, déplacées, renommées ou supprimées."
+        }
+        "Properties" => "Propriétés",
         "Title" => "Titre",
-        "Subject" => "Calcul du classeur",
-        "Author" => "Automatique",
-        "Company" => "Convertir en commentaires",
-        "Keywords" => "Plus de classeurs",
-        "Description" => "Télécharger",
-        "No workbook is open." => "Nombre de pages",
-        "Save as type" => "Enregistrer le classeur sous forme de page web.",
-        "Excel Workbook (*.xlsx)" => "Exporter",
-        "CSV UTF-8 (Comma delimited) (*.csv)" => "Les paramètres de calcul sont enregistrés avec le classeur.",
+        "Subject" => "Sujet",
+        "Author" => "Auteur",
+        "Company" => "Société",
+        "Keywords" => "Mots-clés",
+        "Description" => "Description",
+        "No workbook is open." => "Aucun classeur n'est ouvert.",
+        "Save as type" => "Type de fichier",
+        "Excel Workbook (*.xlsx)" => "Classeur Excel (*.xlsx)",
+        "CSV UTF-8 (Comma delimited) (*.csv)" => "CSV UTF-8 (séparateur point-virgule) (*.csv)",
         "Web Page (*.html)" => "Page web (*.html)",
-        "PDF (*.pdf)" => "Page {page} sur {pages}",
-        "Download" => "Faites glisser pour figer les colonnes",
-        "A CSV file, web page or PDF is a copy: the workbook keeps its own file." => "Ajouter un pied de page",
-        "Save the workbook under another name or in another folder." => "Feuille de droite à gauche",
-        "Print Active Sheets" => "Protéger le classeur",
-        "Print Entire Workbook" => "Récents",
-        "Fit Sheet on One Page" => "Pied de page",
-        "Page Setup…" => "Précédent",
-        "Page {page} of {pages}" => "Commentaire précédent",
-        "Nothing to print." => "Ouvrir",
-        "Previous page" => "Propriétés",
-        "Next page" => "Pas encore enregistré",
-        "Create PDF" => "Date actuelle",
-        "Save the sheet as a PDF document that keeps its page layout." => "Sélectionner\nles données",
-        "Change File Type" => "Case à cocher",
-        "CSV (Comma delimited)" => "CSV UTF-8 (séparé par des virgules) (*.csv)",
-        "Save the active sheet as comma-separated text." => "Enregistrer le classeur sous un autre nom ou dans un autre dossier.",
+        "PDF (*.pdf)" => "PDF (*.pdf)",
+        "Download" => "Télécharger",
+        "A CSV file, web page or PDF is a copy: the workbook keeps its own file." => {
+            "Un fichier CSV, une page web ou un PDF est une copie : le classeur conserve son propre fichier."
+        }
+        "Save the workbook under another name or in another folder." => "Enregistrer le classeur sous un autre nom ou dans un autre dossier.",
+        "Print Active Sheets" => "Imprimer les feuilles actives",
+        "Print Entire Workbook" => "Imprimer tout le classeur",
+        "Fit Sheet on One Page" => "Ajuster la feuille sur une page",
+        "Page Setup…" => "Mise en page…",
+        "Page {page} of {pages}" => "Page {page} sur {pages}",
+        "Nothing to print." => "Rien à imprimer.",
+        "Previous page" => "Page précédente",
+        "Next page" => "Page suivante",
+        "Create PDF" => "Créer un PDF",
+        "Save the sheet as a PDF document that keeps its page layout." => {
+            "Enregistrer la feuille en tant que document PDF qui conserve sa mise en page."
+        }
+        "Change File Type" => "Changer le type de fichier",
+        "CSV (Comma delimited)" => "CSV (séparateur point-virgule)",
+        "Save the active sheet as comma-separated text." => "Enregistrer la feuille active sous forme de texte séparé par des points-virgules.",
         "Web Page (.html)" => "Page web (.html)",
-        "Save the workbook as a web page." => "Nom de la feuille",
-        "Options|General" => "Numéro de page",
-        "Options|Save" => "Mise en page…",
-        "Show formula bar" => "Page web (*.html)",
-        "Save .xlsx workbooks automatically after every change" => "Enregistrer la feuille active sous forme de texte séparé par des virgules.",
+        "Save the workbook as a web page." => "Enregistrer le classeur en tant que page web.",
+        "Options|General" => "Options|Général",
+        "Options|Save" => "Options|Enregistrer",
+        "Show formula bar" => "Afficher la barre de formule",
+        "Save .xlsx workbooks automatically after every change" => "Enregistrer automatiquement les classeurs .xlsx après chaque modification",
         "Workbook calculation" => "Calcul du classeur",
-        "Enable iterative calculation" => "Classeur Excel (*.xlsx)",
-        "Calculation settings are saved with the workbook." => "Modifier le type de fichier",
+        "Enable iterative calculation" => "Activer le calcul itératif",
+        "Calculation settings are saved with the workbook." => "Les paramètres de calcul sont enregistrés avec le classeur.",
         _ => return None,
     })
 }
diff --git a/crates/ui-egui/src/i18n/ko.rs b/crates/ui-egui/src/i18n/ko.rs
index b684c78..f3e1688 100644
--- a/crates/ui-egui/src/i18n/ko.rs
+++ b/crates/ui-egui/src/i18n/ko.rs
@@ -121,6 +121,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "개체\n선택",
         "Themes" => "테마",
         "Margins" => "여백",
+        "Left Margin" => "왼쪽 여백",
+        "Right Margin" => "오른쪽 여백",
+        "Top Margin" => "위쪽 여백",
+        "Bottom Margin" => "아래쪽 여백",
+        "Header Margin" => "머리글 여백",
+        "Footer Margin" => "바닥글 여백",
         "Size" => "용지 크기",
         "Print\nArea" => "인쇄\n영역",
         "Set Print Area" => "인쇄 영역 설정",
diff --git a/crates/ui-egui/src/i18n/pt.rs b/crates/ui-egui/src/i18n/pt.rs
index b554ef9..9ab5b7b 100644
--- a/crates/ui-egui/src/i18n/pt.rs
+++ b/crates/ui-egui/src/i18n/pt.rs
@@ -122,6 +122,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "Selecionar\nObjetos",
         "Themes" => "Temas",
         "Margins" => "Margens",
+        "Left Margin" => "Margem esquerda",
+        "Right Margin" => "Margem direita",
+        "Top Margin" => "Margem superior",
+        "Bottom Margin" => "Margem inferior",
+        "Header Margin" => "Margem do cabeçalho",
+        "Footer Margin" => "Margem do rodapé",
         "Size" => "Tamanho",
         "Print\nArea" => "Área de\nImpressão",
         "Set Print Area" => "Definir Área de Impressão",
@@ -394,6 +400,552 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Workbook calculation" => "Cálculo da pasta de trabalho",
         "Enable iterative calculation" => "Habilitar cálculo iterativo",
         "Calculation settings are saved with the workbook." => "As configurações de cálculo são salvas com a pasta de trabalho.",
+        "OK" => "OK",
+        "Cancel" => "Cancelar",
+        "Don't Save" => "Não Salvar",
+        "Open…" => "Abrir…",
+        "Show password" => "Mostrar senha",
+        "Start a new workbook" => "Criar uma pasta de trabalho",
+        "Household Budget" => "Orçamento Doméstico",
+        "Quarterly Sales Dashboard" => "Painel de Vendas Trimestrais",
+        "Gradebook" => "Boletim de Notas",
+        "this workbook" => "esta pasta de trabalho",
+        "This workbook" => "Esta pasta de trabalho",
+        "Do you want to save the changes you made to {title}?" => "Deseja salvar as alterações feitas em {title}?",
+        "Save a copy as .{format}" => "Salvar uma cópia como .{format}",
+        "Select a chart first." => "Selecione um gráfico primeiro.",
+        "Text Box" => "Caixa de Texto",
+        "Select Data" => "Selecionar Dados",
+        "Row Height" => "Altura da Linha",
+        "Column Width" => "Largura da Coluna",
+        "Standard Width" => "Largura Padrão",
+        "Rename Sheet" => "Renomear Planilha",
+        "Move or Copy" => "Mover ou Copiar",
+        "Protect Sheet" => "Proteger Planilha",
+        "Protect Structure and Windows" => "Proteger Estrutura e Janelas",
+        "Unprotect Workbook" => "Desproteger Pasta de Trabalho",
+        "Unprotect Sheet" => "Desproteger Planilha",
+        "Password" => "Senha",
+        "Unhide" => "Reexibir",
+        "Paste Special" => "Colar Especial",
+        "Series" => "Série",
+        "New Comment" => "Novo Comentário",
+        "Insert Hyperlink" => "Inserir Hiperlink",
+        "Create Sparklines" => "Criar Minigráficos",
+        "Page Setup" => "Configurar Página",
+        "Convert Text to Columns" => "Converter Texto em Colunas",
+        "Remove Duplicates" => "Remover Duplicatas",
+        "Goal Seek" => "Atingir Meta",
+        "Create Forecast Worksheet" => "Criar Planilha de Previsão",
+        "Solver Parameters" => "Parâmetros do Solver",
+        "Solver Results" => "Resultados do Solver",
+        "Edit Name" => "Editar Nome",
+        "New Name" => "Novo Nome",
+        "Format Cells" => "Formatar Células",
+        "Formula Builder" => "Construtor de Fórmulas",
+        "Find and Replace" => "Localizar e Substituir",
+        "Go To" => "Ir para",
+        "Insert Calculated Field" => "Inserir Campo Calculado",
+        "Go To Special" => "Ir para Especial",
+        "Name Manager" => "Gerenciador de Nomes",
+        "Conditional Formatting Rules Manager" => "Gerenciador de Regras de Formatação Condicional",
+        "Search Commands" => "Pesquisar Comandos",
+        "Agent Control" => "Controle por Agentes",
+        "About GridCraft" => "Sobre o GridCraft",
+        "Insert Chart" => "Inserir Gráfico",
+        "Select Data Source" => "Selecionar Fonte de Dados",
+        "Action Journal" => "Registro de Ações",
+        "Macros" => "Macros",
+        "Workbook Statistics" => "Estatísticas da Pasta de Trabalho",
+        "Accessibility" => "Acessibilidade",
+        "Chart Title" => "Título do Gráfico",
+        "Place Picture in Cell" => "Colocar Imagem na Célula",
+        "Place Picture over Cells" => "Colocar Imagem sobre as Células",
+        "Pick From List" => "Escolher na Lista",
+        "Save a Copy" => "Salvar uma Cópia",
+        "Save Changes?" => "Salvar Alterações?",
+        "Shift cells right" => "Deslocar células para a direita",
+        "Shift cells down" => "Deslocar células para baixo",
+        "Shift cells left" => "Deslocar células para a esquerda",
+        "Shift cells up" => "Deslocar células para cima",
+        "Entire row" => "Linha inteira",
+        "Entire column" => "Coluna inteira",
+        "Row height (pixels):" => "Altura da linha (pixels):",
+        "Column width (characters):" => "Largura da coluna (caracteres):",
+        "Standard column width (pixels):" => "Largura padrão da coluna (pixels):",
+        "Name:" => "Nome:",
+        "Before sheet (position, 0 = first):" => "Antes da planilha (posição, 0 = primeira):",
+        "Create a copy" => "Criar uma cópia",
+        "Sheets: {sheets}" => "Planilhas: {sheets}",
+        "Password (optional):" => "Senha (opcional):",
+        "Password:" => "Senha:",
+        "Allow all users of this sheet to:" => "Permitir que todos os usuários desta planilha possam:",
+        "Format cells" => "Formatar células",
+        "Format columns" => "Formatar colunas",
+        "Format rows" => "Formatar linhas",
+        "Insert rows" => "Inserir linhas",
+        "Delete rows" => "Excluir linhas",
+        "Use AutoFilter" => "Usar AutoFiltro",
+        " (password, unlocked)" => " (senha, desbloqueado)",
+        " (password)" => " (senha)",
+        "No ranges yet." => "Nenhum intervalo ainda.",
+        "Ranges that stay editable when the sheet is protected:" => "Intervalos que continuam editáveis quando a planilha está protegida:",
+        "Action" => "Ação",
+        "Modify" => "Modificar",
+        "Unlock with password" => "Desbloquear com senha",
+        "Title:" => "Título:",
+        "Refers to cells:" => "Refere-se às células:",
+        "Range password:" => "Senha do intervalo:",
+        "New title (Modify):" => "Novo título (Modificar):",
+        "Remove the password (Modify)" => "Remover a senha (Modificar)",
+        "'{file}' is protected." => "'{file}' está protegido.",
+        "Unhide sheet:" => "Reexibir planilha:",
+        "Hidden: {sheets}" => "Ocultas: {sheets}",
+        "All" => "Tudo",
+        "Formulas (F)" => "Fórmulas (F)",
+        "Values (V)" => "Valores (V)",
+        "Formats (T)" => "Formatos (T)",
+        "Comments and notes (C)" => "Comentários e notas (C)",
+        "Validation" => "Validação",
+        "All except borders" => "Tudo, exceto bordas",
+        "Column widths" => "Larguras da coluna",
+        "Formulas and number formats" => "Fórmulas e formatos de número",
+        "Values and number formats" => "Valores e formatos de número",
+        "Operation" => "Operação",
+        "Add" => "Adicionar",
+        "Subtract" => "Subtrair",
+        "Multiply" => "Multiplicar",
+        "Divide" => "Dividir",
+        "Skip blanks" => "Ignorar em branco",
+        "Transpose (E)" => "Transpor (E)",
+        "Series in" => "Série em",
+        "Columns" => "Colunas",
+        "Rows" => "Linhas",
+        "Type" => "Tipo",
+        "Linear" => "Linear",
+        "Growth" => "Crescimento",
+        "Date unit" => "Unidade de data",
+        "Day" => "Dia",
+        "Weekday" => "Dia da semana",
+        "Month" => "Mês",
+        "Year" => "Ano",
+        "Step value:" => "Incremento:",
+        "Stop value:" => "Limite:",
+        "Start a conversation:" => "Iniciar uma conversa:",
+        "Note:" => "Nota:",
+        "Display:" => "Texto para exibição:",
+        "Link to (web address, e-mail or Sheet!A1):" => "Vincular a (endereço da Web, e-mail ou Planilha!A1):",
+        "ScreenTip:" => "Dica de tela:",
+        "Data Range:" => "Intervalo de dados:",
+        "Location Range:" => "Intervalo de local:",
+        "Markers" => "Marcadores",
+        "Footer:" => "Rodapé:",
+        "Left margin (in):" => "Margem esquerda (pol.):",
+        "Right margin (in):" => "Margem direita (pol.):",
+        "Top margin (in):" => "Margem superior (pol.):",
+        "Bottom margin (in):" => "Margem inferior (pol.):",
+        "Header (in):" => "Cabeçalho (pol.):",
+        "Footer (in):" => "Rodapé (pol.):",
+        "Tab" => "Tabulação",
+        "Semicolon" => "Ponto e vírgula",
+        "Comma" => "Vírgula",
+        "Space" => "Espaço",
+        "Other:" => "Outros:",
+        "Treat consecutive delimiters as one" => "Considerar delimitadores consecutivos como um só",
+        "Destination:" => "Destino:",
+        "My data has headers" => "Meus dados contêm cabeçalhos",
+        "Columns (blank = all, e.g. A,C):" => "Colunas (em branco = todas, p. ex. A,C):",
+        "Timeline range (blank: first column of the selection):" => "Intervalo da linha do tempo (em branco: primeira coluna da seleção):",
+        "Values range (blank: second column of the selection):" => "Intervalo de valores (em branco: segunda coluna da seleção):",
+        "Confidence interval" => "Intervalo de confiança",
+        "Confidence level (%):" => "Nível de confiança (%):",
+        "Seasonality (auto, 0 for none, or a season length):" => "Sazonalidade (automática, 0 para nenhuma ou a duração de um período):",
+        "Fill missing points using" => "Preencher pontos ausentes usando",
+        "Interpolation" => "Interpolação",
+        "Zeros" => "Zeros",
+        "Aggregate duplicates using" => "Agregar duplicatas usando",
+        "Average" => "Média",
+        "Count" => "Contagem",
+        "CountA" => "Cont.Valores",
+        "Max" => "Máx",
+        "Median" => "Mediana",
+        "Min" => "Mín",
+        "Sum" => "Soma",
+        "Product" => "Produto",
+        "Include forecast statistics" => "Incluir estatísticas de previsão",
+        "Chart" => "Gráfico",
+        "Line chart" => "Gráfico de linhas",
+        "Column chart" => "Gráfico de colunas",
+        "At each change in (column letter):" => "A cada alteração em (letra da coluna):",
+        "Use function" => "Usar função",
+        "Add subtotal to (columns, e.g. C,D):" => "Adicionar subtotal a (colunas, p. ex. C,D):",
+        "Magnification" => "Ampliação",
+        "Custom (%):" => "Personalizado (%):",
+        "Scope (Workbook or sheet name):" => "Escopo (Pasta de Trabalho ou nome da planilha):",
+        "Comment:" => "Comentário:",
+        "Refers to:" => "Refere-se a:",
+        "Allow" => "Permitir",
+        "Any value" => "Qualquer valor",
+        "Whole number" => "Número inteiro",
+        "Decimal" => "Decimal",
+        "List" => "Lista",
+        "Text length" => "Comprimento do texto",
+        "between" => "está entre",
+        "not between" => "não está entre",
+        "equal to" => "é igual a",
+        "not equal to" => "é diferente de",
+        "greater than" => "é maior do que",
+        "less than" => "é menor do que",
+        "greater than or equal to" => "é maior ou igual a",
+        "less than or equal to" => "é menor ou igual a",
+        "Minimum / Source / Formula:" => "Mínimo / Fonte / Fórmula:",
+        "Maximum:" => "Máximo:",
+        "Ignore blank" => "Ignorar em branco",
+        "In-cell dropdown" => "Menu suspenso na célula",
+        "Input message:" => "Mensagem de entrada:",
+        "Error style" => "Estilo de erro",
+        "Stop" => "Parar",
+        "Warning" => "Aviso",
+        "Information" => "Informações",
+        "Error message:" => "Mensagem de erro:",
+        "Format cells that are (value):" => "Formatar células que são (valor):",
+        "and:" => "e:",
+        "Format cells that contain the text:" => "Formatar células que contêm o texto:",
+        "Format cells that contain a date occurring:" => "Formatar células que contêm uma data:",
+        "Yesterday" => "Ontem",
+        "Today" => "Hoje",
+        "Tomorrow" => "Amanhã",
+        "In the last 7 days" => "Nos últimos 7 dias",
+        "Last week" => "Semana passada",
+        "This week" => "Esta semana",
+        "Next week" => "Próxima semana",
+        "Last month" => "Mês passado",
+        "This month" => "Este mês",
+        "Next month" => "Próximo mês",
+        "Format values where this formula is true:" => "Formatar valores em que esta fórmula é verdadeira:",
+        "with" => "com",
+        "Light Red Fill with Dark Red Text" => "Preenchimento Vermelho Claro e Texto Vermelho Escuro",
+        "Yellow Fill with Dark Yellow Text" => "Preenchimento Amarelo e Texto Amarelo Escuro",
+        "Green Fill with Dark Green Text" => "Preenchimento Verde e Texto Verde Escuro",
+        "Light Red Fill" => "Preenchimento Vermelho Claro",
+        "Red Text" => "Texto Vermelho",
+        "Red Border" => "Borda Vermelha",
+        "Formula:" => "Fórmula:",
+        "Select" => "Selecionar",
+        "Blanks" => "Células em branco",
+        "Errors" => "Erros",
+        "Numbers" => "Números",
+        "Current region" => "Região atual",
+        "Last cell" => "Última célula",
+        "Visible cells only" => "Somente células visíveis",
+        "Conditional formats" => "Formatos condicionais",
+        "Data validation" => "Validação de dados",
+        "Horizontal axis title:" => "Título do eixo horizontal:",
+        "Vertical axis title:" => "Título do eixo vertical:",
+        "No picture selected" => "Nenhuma imagem selecionada",
+        "Picture file path (PNG or JPEG):" => "Caminho do arquivo de imagem (PNG ou JPEG):",
+        "Description (optional):" => "Descrição (opcional):",
+        "Fits inside the selected cell and moves with its content." => "Ajusta-se dentro da célula selecionada e move-se com o conteúdo dela.",
+        "Choose a PNG or JPEG no larger than 16 MB." => "Escolha um PNG ou JPEG de no máximo 16 MB.",
+        "About" => "Sobre",
+        "Contributors" => "Colaboradores",
+        "Models" => "Modelos",
+        "Version {version}" => "Versão {version}",
+        "Join the ArtCraft Discord" => "Participe do Discord da ArtCraft",
+        "This workbook has no scripts or macros." => "Esta pasta de trabalho não tem scripts nem macros.",
+        "(unnamed)" => "(sem nome)",
+        "— VBA project (preserved, not run)" => "— Projeto VBA (preservado, não executado)",
+        "— 1 step" => "— 1 etapa",
+        "— {steps} steps" => "— {steps} etapas",
+        "Alignment" => "Alinhamento",
+        "Font" => "Fonte",
+        "Border" => "Borda",
+        "Format Cells|Fill" => "Preenchimento",
+        "Protection" => "Proteção",
+        "Category:" => "Categoria:",
+        "Sample" => "Exemplo",
+        "Type (custom format code):" => "Tipo (código de formato personalizado):",
+        "Vertical" => "Vertical",
+        "Justify" => "Justificar",
+        "Center Across Selection" => "Centralizar Seleção",
+        "Distributed" => "Distribuído",
+        "Top" => "Superior",
+        "Bottom" => "Inferior",
+        "Indent" => "Recuo",
+        "Orientation (degrees)" => "Orientação (graus)",
+        "Wrap text" => "Quebrar texto automaticamente",
+        "Shrink to fit" => "Reduzir para caber",
+        "Bold" => "Negrito",
+        "Italic" => "Itálico",
+        "None" => "Nenhum",
+        "Single" => "Simples",
+        "Double" => "Duplo",
+        "Single Accounting" => "Simples (Contábil)",
+        "Double Accounting" => "Duplo (Contábil)",
+        "Superscript" => "Sobrescrito",
+        "Subscript" => "Subscrito",
+        "Color:" => "Cor:",
+        "Outline" => "Contorno",
+        "Diagonal ↘" => "Diagonal ↘",
+        "Diagonal ↗" => "Diagonal ↗",
+        "none" => "nenhuma",
+        "thin" => "fina",
+        "medium" => "média",
+        "thick" => "espessa",
+        "dashed" => "tracejada",
+        "dotted" => "pontilhada",
+        "double" => "dupla",
+        "Background Color:" => "Cor do plano de fundo:",
+        "Locked" => "Bloqueadas",
+        "Hidden" => "Ocultas",
+        "Search:" => "Pesquisar:",
+        "e.g. lookup, average, date" => "p. ex. pesquisa, média, data",
+        "Date & Time" => "Data e Hora",
+        "Lookup & Reference" => "Pesquisa e Referência",
+        "Math & Trig" => "Matemática e Trigonometria",
+        "Statistical" => "Estatística",
+        "Engineering" => "Engenharia",
+        "Database" => "Banco de Dados",
+        "Compatibility" => "Compatibilidade",
+        "Web" => "Web",
+        "Cube" => "Cubo",
+        "Add-in and Automation" => "Suplemento e Automação",
+        "Find" => "Localizar",
+        "Replace" => "Substituir",
+        "Find what:" => "Localizar:",
+        "Replace with:" => "Substituir por:",
+        "Match case" => "Diferenciar maiúsculas e minúsculas",
+        "Match entire cell contents" => "Coincidir conteúdo da célula inteira",
+        "Within workbook" => "Na pasta de trabalho",
+        "Replace All" => "Substituir Tudo",
+        "Find All" => "Localizar Tudo",
+        "Find Next" => "Localizar Próxima",
+        "All done. We made {count} replacements." => "Tudo pronto. Fizemos {count} substituições.",
+        "{count} cell(s) found" => "{count} célula(s) encontrada(s)",
+        "Reference:" => "Referência:",
+        "Special…" => "Especial…",
+        "My list has headers" => "Meus dados contêm cabeçalhos",
+        "Sort by" => "Classificar por",
+        "Then by" => "E depois por",
+        "Cell Values" => "Valores de Célula",
+        "Cell Color" => "Cor da Célula",
+        "A to Z" => "De A a Z",
+        "Z to A" => "De Z a A",
+        "+ Add Level" => "+ Adicionar Nível",
+        "New…" => "Novo…",
+        "Edit…" => "Editar…",
+        "Name" => "Nome",
+        "Value" => "Valor",
+        "Refers To" => "Refere-se a",
+        "Scope" => "Escopo",
+        "Workbook" => "Pasta de Trabalho",
+        "No names defined" => "Nenhum nome definido",
+        "Recommended Charts" => "Gráficos Recomendados",
+        "All Charts" => "Todos os Gráficos",
+        "Clustered Column" => "Colunas Agrupadas",
+        "Stacked Column" => "Colunas Empilhadas",
+        "100% Stacked Column" => "Colunas 100% Empilhadas",
+        "Clustered Bar" => "Barras Agrupadas",
+        "Stacked Bar" => "Barras Empilhadas",
+        "100% Stacked Bar" => "Barras 100% Empilhadas",
+        "Line" => "Linhas",
+        "Line with Markers" => "Linhas com Marcadores",
+        "Stacked Line" => "Linhas Empilhadas",
+        "Pie" => "Pizza",
+        "Doughnut" => "Rosca",
+        "Area" => "Área",
+        "Stacked Area" => "Área Empilhada",
+        "Scatter" => "Dispersão",
+        "Scatter with Lines" => "Dispersão com Linhas",
+        "Radar" => "Radar",
+        "Histogram" => "Histograma",
+        "Waterfall" => "Cascata",
+        "Funnel" => "Funil",
+        "Combo" => "Combinação",
+        "Chart data range:" => "Intervalo de dados do gráfico:",
+        "Legend Entries (Series)" => "Entradas de Legenda (Série)",
+        "Series{n}" => "Série{n}",
+        "Keep" => "Manter",
+        "Remove" => "Remover",
+        "Horizontal (Category) Axis Labels:" => "Rótulos do Eixo Horizontal (Categorias):",
+        "There are no conditional formatting rules on this sheet." => "Não há regras de formatação condicional nesta planilha.",
+        "applies to" => "aplica-se a",
+        "Type a command, e.g. freeze, chart, bold…" => "Digite um comando, p. ex. congelar, gráfico, negrito…",
+        "Set cell:" => "Definir célula:",
+        "To value:" => "Para valor:",
+        "By changing cell:" => "Alternando célula:",
+        "Goal Seeking found a solution: {value}" => "Atingir Meta encontrou uma solução: {value}",
+        "Analysis Tools" => "Ferramentas de Análise",
+        "Anova: Single Factor" => "Anova: fator único",
+        "Correlation" => "Correlação",
+        "Covariance" => "Covariância",
+        "Descriptive Statistics" => "Estatística descritiva",
+        "Exponential Smoothing" => "Ajuste exponencial",
+        "F-Test Two-Sample for Variances" => "Teste F: duas amostras para variâncias",
+        "Moving Average" => "Média móvel",
+        "Rank and Percentile" => "Ordem e percentil",
+        "Regression" => "Regressão",
+        "t-Test: Paired Two Sample for Means" => "Teste t: duas amostras em par para médias",
+        "t-Test: Two-Sample Assuming Equal Variances" => "Teste t: duas amostras presumindo variâncias equivalentes",
+        "t-Test: Two-Sample Assuming Unequal Variances" => "Teste t: duas amostras presumindo variâncias diferentes",
+        "Output options" => "Opções de saída",
+        "Output Range:" => "Intervalo de saída:",
+        "New Worksheet Ply:" => "Nova planilha:",
+        "Grouped By:" => "Agrupado por:",
+        "Labels in first row" => "Rótulos na primeira linha",
+        "Input Range:" => "Intervalo de entrada:",
+        "Variable 1 Range:" => "Intervalo da variável 1:",
+        "Variable 2 Range:" => "Intervalo da variável 2:",
+        "Summary statistics" => "Resumo estatístico",
+        "Confidence Level for Mean (%), blank for none:" => "Nível de confiabilidade para a média (%), em branco para nenhum:",
+        "Kth Largest (blank for none):" => "K-ésimo maior (em branco para nenhum):",
+        "Kth Smallest (blank for none):" => "K-ésimo menor (em branco para nenhum):",
+        "Bin Range (blank for automatic bins):" => "Intervalo do bloco (em branco para blocos automáticos):",
+        "Pareto (sorted histogram)" => "Pareto (histograma classificado)",
+        "Cumulative Percentage" => "Porcentagem cumulativa",
+        "Alpha:" => "Alfa:",
+        "Input Y Range:" => "Intervalo Y de entrada:",
+        "Input X Range:" => "Intervalo X de entrada:",
+        "Constant is Zero" => "Constante é zero",
+        "Confidence Level (%):" => "Nível de confiança (%):",
+        "Residuals" => "Resíduos",
+        "Standardized Residuals" => "Resíduos padronizados",
+        "Normal Probability" => "Plotagem de probabilidade normal",
+        "Interval:" => "Intervalo:",
+        "Standard Errors" => "Erros padrão",
+        "Damping factor:" => "Fator de amortecimento:",
+        "Hypothesized Mean Difference:" => "Hipótese da diferença de média:",
+        "Set Objective:" => "Definir Objetivo:",
+        "To:" => "Para:",
+        "Value Of:" => "Valor de:",
+        "By Changing Variable Cells:" => "Alterando Células Variáveis:",
+        "Subject to the Constraints:" => "Sujeito às Restrições:",
+        "Make Unconstrained Variables Non-Negative" => "Tornar Variáveis Irrestritas Não Negativas",
+        "Select a Solving Method:" => "Selecionar um Método de Solução:",
+        "GRG Nonlinear" => "GRG Não Linear",
+        "Solve" => "Resolver",
+        "Keep Solver Solution" => "Manter Solução do Solver",
+        "Restore Original Values" => "Restaurar Valores Originais",
+        "The spelling check is complete for the entire sheet." => "A verificação ortográfica da planilha inteira foi concluída.",
+        "Not in Dictionary ({cell}):" => "Não consta no dicionário ({cell}):",
+        "Suggestions:" => "Sugestões:",
+        "(No suggestions)" => "(Nenhuma sugestão)",
+        "Ignore Once" => "Ignorar uma vez",
+        "Add to Dictionary" => "Adicionar ao dicionário",
+        "Change" => "Alterar",
+        "Change All" => "Alterar todas",
+        "$ English (United States)" => "$ Inglês (Estados Unidos)",
+        "Add Chart Element" => "Adicionar Elemento Gráfico",
+        "Align Left" => "Alinhar à Esquerda",
+        "Align Right" => "Alinhar à Direita",
+        "Bottom Align" => "Alinhar Embaixo",
+        "Calculate Now (F9)" => "Calcular Agora (F9)",
+        "Calculate Sheet (⇧F9)" => "Calcular Planilha (⇧F9)",
+        "Calculation Options" => "Opções de Cálculo",
+        "Cell Styles" => "Estilos de Célula",
+        "Change Chart Type" => "Alterar Tipo de Gráfico",
+        "Check Accessibility" => "Verificar Acessibilidade",
+        "Clear Filter" => "Limpar Filtro",
+        "Column or Bar" => "Coluna ou Barra",
+        "Comments pane" => "Painel de comentários",
+        "Convert the last ink stroke to a shape" => "Converter o último traço de tinta em forma",
+        "Convert to Range" => "Converter em Intervalo",
+        "Copy" => "Copiar",
+        "Custom Sort" => "Classificação Personalizada",
+        "Cut" => "Recortar",
+        "Define Name…" => "Definir Nome…",
+        "Delete Comment" => "Excluir Comentário",
+        "Delete Sheet" => "Excluir Planilha",
+        "Delete chart" => "Excluir gráfico",
+        "Delete…" => "Excluir…",
+        "Dismiss" => "Fechar",
+        "Down" => "Para Baixo",
+        "Edit chart title" => "Editar título do gráfico",
+        "Erase ink strokes" => "Apagar traços de tinta",
+        "Every command run in this session (replayable)" => "Todos os comandos executados nesta sessão (podem ser repetidos)",
+        "Expand formula bar" => "Expandir barra de fórmulas",
+        "Filter (⌘⇧F)" => "Filtro (⌘⇧F)",
+        "Filter by Selected Cell's Value" => "Filtrar pelo Valor da Célula Selecionada",
+        "Find & Select" => "Localizar e Selecionar",
+        "Flash Fill (⌘E)" => "Preenchimento Relâmpago (⌘E)",
+        "Forecast Sheet" => "Planilha de Previsão",
+        "Forecast end (date or number; blank: a third of the history):" => "Fim da previsão (data ou número; em branco: um terço do histórico):",
+        "Format Chart pane" => "Painel Formatar Gráfico",
+        "Format as Table" => "Formatar como Tabela",
+        "Hide" => "Ocultar",
+        "Hide Sheet" => "Ocultar Planilha",
+        "Hierarchy & more" => "Hierarquia e mais",
+        "Highlighter" => "Marca-texto",
+        "How agents drive GridCraft (MCP / control channel)" => "Como os agentes controlam o GridCraft (MCP / canal de controle)",
+        "Import a text or CSV file" => "Importar um arquivo de texto ou CSV",
+        "Insert Function" => "Inserir Função",
+        "Insert Function (⇧F3)" => "Inserir Função (⇧F3)",
+        "Insert Link (⌘K)" => "Inserir Link (⌘K)",
+        "Insert Sheet" => "Inserir Planilha",
+        "Insert Slicer" => "Inserir Segmentação de Dados",
+        "Insert a picture" => "Inserir uma imagem",
+        "Insert a slicer to filter a table" => "Inserir uma segmentação de dados para filtrar uma tabela",
+        "Insert an icon" => "Inserir um ícone",
+        "Insert…" => "Inserir…",
+        "Line or Area" => "Linha ou Área",
+        "Link…" => "Link…",
+        "Macros and scripts in this workbook (Alt+F8)" => "Macros e scripts nesta pasta de trabalho (Alt+F8)",
+        "Middle Align" => "Alinhar no Meio",
+        "More commands" => "Mais comandos",
+        "Move or Copy Sheet…" => "Mover ou Copiar Planilha…",
+        "New sheet (⇧F11)" => "Nova planilha (⇧F11)",
+        "Next sheet" => "Próxima planilha",
+        "Page Breaks" => "Quebras",
+        "Paper Size" => "Tamanho",
+        "Paste (⌘V)" => "Colar (⌘V)",
+        "Pick From Drop-down List…" => "Escolher na Lista Suspensa…",
+        "Pie or Doughnut" => "Pizza ou Rosca",
+        "Previous sheet" => "Planilha anterior",
+        "Print Area" => "Área de Impressão",
+        "Print Titles" => "Imprimir Títulos",
+        "Protect Workbook structure" => "Proteger estrutura da pasta de trabalho",
+        "Redo (⌘Y)" => "Refazer (⌘Y)",
+        "Save (⌘S)" => "Salvar (⌘S)",
+        "Scatter or Bubble" => "Dispersão ou Bolhas",
+        "Search and run any command" => "Pesquisar e executar qualquer comando",
+        "Search commands (⌘⇧Space)" => "Pesquisar comandos (⌘⇧Space)",
+        "Select and move ink and shapes" => "Selecionar e mover tinta e formas",
+        "Series…" => "Série…",
+        "Share: export or save a copy" => "Compartilhar: exportar ou salvar uma cópia",
+        "Show Formulas (⌃`)" => "Mostrar Fórmulas (⌃`)",
+        "Slicer" => "Segmentação de Dados",
+        "Sort & Filter" => "Classificar e Filtrar",
+        "Spelling (F7)" => "Ortografia (F7)",
+        "Statistic" => "Estatístico",
+        "Switch Row/Column" => "Alternar Linha/Coluna",
+        "Table (⌘T)" => "Tabela (⌘T)",
+        "Table Styles" => "Estilos de Tabela",
+        "Text to Columns" => "Texto para Colunas",
+        "The output range already holds data. Replace it with the report?" => "O intervalo de saída já contém dados. Substituí-los pelo relatório?",
+        "Top Align" => "Alinhar em Cima",
+        "Undo (⌘Z)" => "Desfazer (⌘Z)",
+        "Undo list" => "Lista de desfazer",
+        "Unhide Sheet…" => "Reexibir Planilha…",
+        "Up" => "Para Cima",
+        "Version, contributors and the AI models that helped" => "Versão, colaboradores e os modelos de IA que ajudaram",
+        "What-If Analysis" => "Teste de Hipóteses",
+        "Zoom In" => "Ampliar",
+        "Zoom Out" => "Reduzir",
+        "Zoom to 100%" => "Zoom em 100%",
+        "Zoom to Selection" => "Zoom na Seleção",
+        "Zoom…" => "Zoom…",
+        "£ English (United Kingdom)" => "£ Inglês (Reino Unido)",
+        "¥ Japanese" => "¥ Japonês",
+        "€ Euro" => "€ Euro",
+        "Tab|Insert" => "Inserir",
+        "AutoSave" => "Salvamento Automático",
+        "Insert\nSlicer" => "Inserir\nSegmentação",
+        "Pen\nBlack" => "Caneta\nPreta",
+        "Pen\nBlue" => "Caneta\nAzul",
+        "Pen\nRed" => "Caneta\nVermelha",
+        "Protect\nSheet" => "Proteger\nPlanilha",
+        "Watch\nWindow" => "Janela de\nInspeção",
+        "Workbook\nStatistics" => "Estatísticas da\nPasta de Trabalho",
         _ => return None,
     })
 }
diff --git a/crates/ui-egui/src/i18n/ru.rs b/crates/ui-egui/src/i18n/ru.rs
index c8f0445..868f653 100644
--- a/crates/ui-egui/src/i18n/ru.rs
+++ b/crates/ui-egui/src/i18n/ru.rs
@@ -121,6 +121,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "Выбрать\nобъекты",
         "Themes" => "Темы",
         "Margins" => "Поля",
+        "Left Margin" => "Левое поле",
+        "Right Margin" => "Правое поле",
+        "Top Margin" => "Верхнее поле",
+        "Bottom Margin" => "Нижнее поле",
+        "Header Margin" => "Поле верхнего колонтитула",
+        "Footer Margin" => "Поле нижнего колонтитула",
         "Size" => "Размер",
         "Print\nArea" => "Область\nпечати",
         "Set Print Area" => "Задать область печати",
diff --git a/crates/ui-egui/src/i18n/sr.rs b/crates/ui-egui/src/i18n/sr.rs
new file mode 100644
index 0000000..bc6a8ee
--- /dev/null
+++ b/crates/ui-egui/src/i18n/sr.rs
@@ -0,0 +1,396 @@
+//! Serbian (Latin script, ekavian) translations for the interface strings in i18n.rs.
+
+pub(super) fn translate(text: &str) -> Option<&'static str> {
+    Some(match text {
+        "Paste" => "Nalepi",
+        "Paste Values" => "Nalepi vrednosti",
+        "Paste Formulas" => "Nalepi formule",
+        "Paste Formatting" => "Nalepi oblikovanje",
+        "Transpose" => "Transponuj",
+        "Paste Link" => "Nalepi vezu",
+        "Paste Special…" => "Specijalno lepljenje…",
+        "Insert Copied Cells" => "Umetni kopirane ćelije",
+        "Insert Copied Cells…" => "Umetni kopirane ćelije…",
+        "Insert Cut Cells" => "Umetni isečene ćelije",
+        "Insert Paste" => "Umetni lepljenje",
+        "Cut (⌘X)" => "Iseci (⌘X)",
+        "Copy (⌘C)" => "Kopiraj (⌘C)",
+        "Format Painter (double-click to keep it on)" => "Kopiraj oblikovanje (dupli klik da ostane uključeno)",
+        "Bold (⌘B)" => "Podebljano (⌘B)",
+        "Italic (⌘I)" => "Kurziv (⌘I)",
+        "Underline (⌘U)" => "Podvučeno (⌘U)",
+        "Double Underline" => "Dvostruko podvlačenje",
+        "Strikethrough" => "Precrtano",
+        "Underline" => "Podvučeno",
+        "Increase Font Size" => "Povećaj veličinu fonta",
+        "Decrease Font Size" => "Smanji veličinu fonta",
+        "Wrap Text" => "Prelomi tekst",
+        "Merge & Center" => "Spoji i centriraj",
+        "Merge Cells" => "Spoji ćelije",
+        "Merge Across" => "Spoji po redovima",
+        "Unmerge Cells" => "Razdvoji ćelije",
+        "Fill Color" => "Boja popune",
+        "Font Color" => "Boja fonta",
+        "Borders" => "Ivice",
+        "Top\nAlign" => "Gornje\nporavnanje",
+        "Middle\nAlign" => "Srednje\nporavnanje",
+        "Bottom\nAlign" => "Donje\nporavnanje",
+        "Left" => "Levo",
+        "Right" => "Desno",
+        "Center" => "Centrirano",
+        "Horizontal" => "Horizontalno",
+        "Vertical Text" => "Vertikalni tekst",
+        "Decrease Indent" => "Smanji uvlačenje",
+        "Increase Indent" => "Povećaj uvlačenje",
+        "Orientation" => "Orijentacija",
+        "Page Layout|Orientation" => "Orijentacija",
+        "Angle Counterclockwise" => "Ugao u levo",
+        "Angle Clockwise" => "Ugao u desno",
+        "Rotate Text Up" => "Rotiraj tekst nagore",
+        "Rotate Text Down" => "Rotiraj tekst nadole",
+        "Accounting Number Format" => "Računovodstveni format",
+        "Percent Style" => "Procentualni stil",
+        "Comma Style" => "Stil sa zapetama",
+        "Increase Decimal" => "Povećaj decimale",
+        "Decrease Decimal" => "Smanji decimale",
+        "More Accounting Formats…" => "Još računovodstvenih formata…",
+        "Conditional\nFormatting" => "Uslovno\noblikovanje",
+        "Conditional Formatting" => "Uslovno oblikovanje",
+        "Format\nas Table" => "Oblikuj\nkao tabelu",
+        "Cell\nStyles" => "Stilovi\nćelija",
+        "Format Cells…" => "Oblikovanje ćelija…",
+        "Format Cell Alignment…" => "Oblikovanje poravnanja ćelije…",
+        "Format\nPane" => "Okno za\noblikovanje",
+        "Format" => "Oblikovanje",
+        "Insert" => "Umetni",
+        "Insert Cells…" => "Umetni ćelije…",
+        "Delete" => "Obriši",
+        "Delete Cells…" => "Obriši ćelije…",
+        "Insert Sheet Rows" => "Umetni redove lista",
+        "Insert Sheet Columns" => "Umetni kolone lista",
+        "Delete Sheet Rows" => "Obriši redove lista",
+        "Delete Sheet Columns" => "Obriši kolone lista",
+        "Row Height…" => "Visina reda…",
+        "AutoFit Row Height" => "Automatsko uklapanje visine reda",
+        "Column Width…" => "Širina kolone…",
+        "AutoFit Column Width" => "Automatsko uklapanje širine kolone",
+        "Default Width…" => "Podrazumevana širina…",
+        "Hide Rows" => "Sakrij redove",
+        "Unhide Rows" => "Otkrij redove",
+        "Hide Columns" => "Sakrij kolone",
+        "Unhide Columns" => "Otkrij kolone",
+        "Lock Cell" => "Zaključaj ćeliju",
+        "Clear" => "Obriši",
+        "Clear All" => "Obriši sve",
+        "Clear Formats" => "Obriši oblikovanja",
+        "Clear Contents" => "Obriši sadržaj",
+        "Clear Comments and Notes" => "Obriši komentare i beleške",
+        "Clear Hyperlinks" => "Obriši hiperveze",
+        "AutoSum" => "Automatski zbir",
+        "AutoSum (⌘⇧T)" => "Automatski zbir (⌘⇧T)",
+        "Flash\nFill" => "Brzo\npopunjavanje",
+        "Flash Fill" => "Brzo popunjavanje",
+        "Fill" => "Popuni",
+        "Clear Print Area" => "Obriši oblast štampe",
+        "Find &\nSelect" => "Pronađi i\nizaberi",
+        "Find…" => "Pronađi…",
+        "Replace…" => "Zameni…",
+        "Go To…" => "Idi na…",
+        "Go To Special…" => "Idi na posebno…",
+        "PivotTable" => "Izvedena tabela",
+        "Recommended\nCharts" => "Preporučeni\ngrafikoni",
+        "Table" => "Tabela",
+        "Pictures" => "Slike",
+        "Shapes" => "Oblici",
+        "Icons" => "Ikone",
+        "Text\nBox" => "Tekstualni\nokvir",
+        "Comment" => "Komentar",
+        "New\nComment" => "Novi\nkomentar",
+        "New Note" => "Nova beleška",
+        "Show/Hide Note" => "Prikaži/sakrij belešku",
+        "Header &\nFooter" => "Zaglavlje i\npodnožje",
+        "Text to\nColumns" => "Tekst u\nkolone",
+        "Link" => "Veza",
+        "Symbol" => "Simbol",
+        "Sparklines" => "Mini grafikoni",
+        "Checkbox" => "Polje za potvrdu",
+        "Insert checkboxes in the selected cells" => "Umetni polja za potvrdu u izabrane ćelije",
+        "Header & Footer" => "Zaglavlje i podnožje",
+        "Draw with ink" => "Crtaj mastilom",
+        "Eraser" => "Gumica",
+        "Ink to\nShape" => "Mastilo u\noblik",
+        "Select\nObjects" => "Izaberi\nobjekte",
+        "Themes" => "Teme",
+        "Margins" => "Margine",
+        "Size" => "Veličina",
+        "Print\nArea" => "Oblast\nštampe",
+        "Set Print Area" => "Postavi oblast štampe",
+        "Breaks" => "Prelomi",
+        "Insert Page Break" => "Umetni prelom stranice",
+        "Remove Page Break" => "Ukloni prelom stranice",
+        "Reset All Page Breaks" => "Resetuj sve prelome stranica",
+        "Print\nTitles" => "Naslovi za\nštampu",
+        "Sheet\nRight-to-Left" => "List\nzdesna nalevo",
+        "Sheet Right-to-Left" => "List zdesna nalevo",
+        "Narrow" => "Usko",
+        "Wide" => "Široko",
+        "Normal" => "Normalno",
+        "Portrait" => "Uspravno",
+        "Landscape" => "Položeno",
+        "Custom Margins…" => "Prilagođene margine…",
+        "Insert\nFunction" => "Umetni\nfunkciju",
+        "Name\nManager" => "Upravljač\nimenima",
+        "Define Name" => "Definiši ime",
+        "Use in Formula" => "Koristi u formuli",
+        "Create from Selection" => "Napravi iz selekcije",
+        "Trace Precedents" => "Prati prethodnike",
+        "Trace Dependents" => "Prati zavisne ćelije",
+        "Remove Arrows" => "Ukloni strelice",
+        "Show Formulas" => "Prikaži formule",
+        "Error Checking" => "Provera grešaka",
+        "Evaluate Formula" => "Proceni formulu",
+        "Watch Window" => "Prozor za praćenje",
+        "Calculation\nOptions" => "Opcije\nizračunavanja",
+        "Calculate Now" => "Izračunaj sada",
+        "Calculate Sheet" => "Izračunaj list",
+        "Automatic" => "Automatski",
+        "Automatic Except for Data Tables" => "Automatski osim za tabele podataka",
+        "Manual" => "Ručno",
+        "Sort &\nFilter" => "Sortiraj i\nfiltriraj",
+        "Sort" => "Sortiraj",
+        "Sort A to Z" => "Sortiraj od A do Š",
+        "Sort Z to A" => "Sortiraj od Š do A",
+        "Custom Sort…" => "Prilagođeno sortiranje…",
+        "Filter" => "Filter",
+        "Reapply" => "Ponovo primeni",
+        "Get Data\n(Text/CSV)" => "Preuzmi podatke\n(Tekst/CSV)",
+        "Remove\nDuplicates" => "Ukloni\nduplikate",
+        "Data\nValidation" => "Provera\npodataka",
+        "Data Validation" => "Provera podataka",
+        "Data Validation…" => "Provera podataka…",
+        "Circle Invalid Data" => "Zaokruži nevažeće podatke",
+        "Clear Validation" => "Ukloni proveru",
+        "Group" => "Grupiši",
+        "Ungroup" => "Razgrupiši",
+        "Show Detail" => "Prikaži detalje",
+        "Hide Detail" => "Sakrij detalje",
+        "Subtotal" => "Međuzbir",
+        "Data\nAnalysis" => "Analiza\npodataka",
+        "Data Analysis" => "Analiza podataka",
+        "Solver" => "Rešavač",
+        "What-If\nAnalysis" => "Analiza\nšta-ako",
+        "Data Table…" => "Tabela podataka…",
+        "Scenario Manager…" => "Upravljač scenarijima…",
+        "Goal Seek…" => "Traženje cilja…",
+        "Forecast\nSheet" => "Prognozni\nlist",
+        "Spelling" => "Pravopis",
+        "Check\nAccessibility" => "Provera\npristupačnosti",
+        "Threaded Comments" => "Komentari u nizu",
+        "Show\nComments" => "Prikaži\nkomentare",
+        "Previous" => "Prethodni",
+        "Next" => "Sledeći",
+        "Previous Comment" => "Prethodni komentar",
+        "Next Comment" => "Sledeći komentar",
+        "Show All Notes" => "Prikaži sve beleške",
+        "Convert to Comments" => "Pretvori u komentare",
+        "Protect\nWorkbook" => "Zaštiti\nradnu svesku",
+        "Allow Edit\nRanges" => "Dozvoli uređivanje\nopsega",
+        "Allow Edit Ranges" => "Dozvoli uređivanje opsega",
+        "Unprotect\nSheet" => "Ukloni zaštitu\nlista",
+        "Protect Sheet…" => "Zaštiti list…",
+        "Comments" => "Komentari",
+        "Notes" => "Beleške",
+        "Page Break\nPreview" => "Pregled preloma\nstranica",
+        "Page\nLayout" => "Izgled\nstranice",
+        "Formula Bar" => "Traka formule",
+        "Gridlines" => "Linije mreže",
+        "Headings" => "Zaglavlja",
+        "Zoom" => "Uvećanje",
+        "100%" => "100%",
+        "Zoom to\nSelection" => "Uvećaj na\nselekciju",
+        "Freeze\nPanes" => "Zamrzni\nokna",
+        "Freeze Panes" => "Zamrzni okna",
+        "Freeze Top Row" => "Zamrzni gornji red",
+        "Freeze First Column" => "Zamrzni prvu kolonu",
+        "Unfreeze Panes" => "Odmrzni okna",
+        "Dark Mode" => "Tamni režim",
+        "Display theme" => "Tema prikaza",
+        "Animations" => "Animacije",
+        "Glide the selection outline to the cell you move to instead of jumping there" => {
+            "Kliziti obris selekcije do ćelije na koju se pomeraš umesto skoka"
+        }
+        "System" => "Sistem",
+        "Light" => "Svetla",
+        "Dark" => "Tamna",
+        "Interface language" => "Jezik interfejsa",
+        "Interface size" => "Veličina interfejsa",
+        "Auto" => "Automatski",
+        "Drag to freeze columns" => "Prevuci da zamrzneš kolone",
+        "Drag to freeze rows" => "Prevuci da zamrzneš redove",
+        "Command\nPalette" => "Paleta\nkomandi",
+        "Agent\nControl" => "Kontrola\nagenta",
+        "Action\nJournal" => "Dnevnik\nradnji",
+        "About\nGridCraft" => "O programu\nGridCraft",
+        "Share" => "Deli",
+        "Add Chart\nElement" => "Dodaj element\ngrafikona",
+        "Change\nChart Type" => "Promeni\ntip grafikona",
+        "Switch\nRow/Column" => "Zameni\nred/kolonu",
+        "Select\nData" => "Izaberi\npodatke",
+        "Data Labels: None" => "Oznake podataka: Ništa",
+        "Data Labels: Show" => "Oznake podataka: Prikaži",
+        "Legend: None" => "Legenda: Ništa",
+        "Legend: Bottom" => "Legenda: Dole",
+        "Legend: Top" => "Legenda: Gore",
+        "Legend: Right" => "Legenda: Desno",
+        "Gridlines: None" => "Linije mreže: Ništa",
+        "Gridlines: Show" => "Linije mreže: Prikaži",
+        "Chart\nTitle" => "Naslov\ngrafikona",
+        "Delete\nChart" => "Obriši\ngrafikon",
+        "Convert\nto Range" => "Pretvori\nu opseg",
+        "Table\nStyles" => "Stilovi\ntabele",
+        "Top 10 Items" => "10 najboljih stavki",
+        "Top 10%" => "Gornjih 10%",
+        "Bottom 10 Items" => "10 najgorih stavki",
+        "Bottom 10%" => "Donjih 10%",
+        "Above Average" => "Iznad proseka",
+        "Below Average" => "Ispod proseka",
+        "Clear Rules from Entire Sheet" => "Obriši pravila sa celog lista",
+        "Clear Rules from Selected Cells" => "Obriši pravila iz izabranih ćelija",
+        "Constants" => "Konstante",
+        "Data Bars" => "Trake podataka",
+        "Color Scales" => "Skale boja",
+        "Icon Sets" => "Skupovi ikona",
+        "Home" => "Početna",
+        "Draw" => "Crtanje",
+        "Page Layout" => "Izgled stranice",
+        "Formulas" => "Formule",
+        "Data" => "Podaci",
+        "Review" => "Pregled",
+        "View" => "Prikaz",
+        "Automate" => "Automatizacija",
+        "Table Design" => "Dizajn tabele",
+        "Chart Design" => "Dizajn grafikona",
+        "Ready" => "Spremno",
+        "Enter" => "Unos",
+        "Edit" => "Uređivanje",
+        "Point" => "Pokaži",
+        "Calculate" => "Izračunavanje",
+        "Select destination and press Enter or choose Paste" => "Izaberi odredište i pritisni Enter ili izaberi Nalepi",
+        "General" => "Opšte",
+        "Number" => "Broj",
+        "Currency" => "Valuta",
+        "Accounting" => "Računovodstveno",
+        "Date" => "Datum",
+        "Time" => "Vreme",
+        "Percentage" => "Procenat",
+        "Fraction" => "Razlomak",
+        "Scientific" => "Naučno",
+        "Text" => "Tekst",
+        "Special" => "Posebno",
+        "Custom" => "Prilagođeno",
+        "Short Date" => "Kratak datum",
+        "Long Date" => "Dugačak datum",
+        "More Number Formats…" => "Još formata brojeva…",
+        "Financial" => "Finansijsko",
+        "Logical" => "Logičko",
+        "Date &\nTime" => "Datum i\nvreme",
+        "Lookup &\nReference" => "Pretraga i\nreference",
+        "Math &\nTrig" => "Matematika i\ntrigonometrija",
+        "More\nFunctions" => "Još\nfunkcija",
+        "Sheet Options|View" => "Opcije lista|Prikaz",
+        "Print" => "Štampaj",
+        "Click to add data" => "Kliknite da dodate podatke",
+        "Add header" => "Dodaj zaglavlje",
+        "Add footer" => "Dodaj podnožje",
+        "(none)" => "(ništa)",
+        "Header" => "Zaglavlje",
+        "Footer" => "Podnožje",
+        "Page\nNumber" => "Broj\nstranice",
+        "Number\nof Pages" => "Broj\nstranica",
+        "Current\nDate" => "Trenutni\ndatum",
+        "Current\nTime" => "Trenutno\nvreme",
+        "File\nPath" => "Putanja\nfajla",
+        "File\nName" => "Ime\nfajla",
+        "Sheet\nName" => "Ime\nlista",
+        "Go to\nHeader" => "Idi na\nzaglavlje",
+        "Go to\nFooter" => "Idi na\npodnožje",
+        "Page Number" => "Broj stranice",
+        "Number of Pages" => "Broj stranica",
+        "Current Date" => "Trenutni datum",
+        "Current Time" => "Trenutno vreme",
+        "File Path" => "Putanja fajla",
+        "File Name" => "Ime fajla",
+        "Sheet Name" => "Ime lista",
+        "Go to Header" => "Idi na zaglavlje",
+        "Different First Page" => "Drugačija prva stranica",
+        "Different Odd & Even Pages" => "Drugačije neparne i parne stranice",
+        "Go to Footer" => "Idi na podnožje",
+        "Ruler" => "Lenjir",
+        "File" => "Datoteka",
+        "Back" => "Nazad",
+        "New" => "Novo",
+        "Open" => "Otvori",
+        "Info" => "Informacije",
+        "Save" => "Sačuvaj",
+        "Save As" => "Sačuvaj kao",
+        "Export" => "Izvezi",
+        "Close" => "Zatvori",
+        "Options" => "Opcije",
+        "Blank workbook" => "Prazna radna sveska",
+        "Recent" => "Nedavno",
+        "No recent workbooks yet." => "Još nema nedavnih radnih svezaka.",
+        "More workbooks" => "Više radnih svezaka",
+        "Browse…" => "Pregledaj…",
+        "Not saved yet" => "Još nije sačuvano",
+        "Location" => "Lokacija",
+        "Sheets" => "Listovi",
+        "Protect Workbook" => "Zaštiti radnu svesku",
+        "Sheet structure is locked: sheets can't be added, moved, renamed or deleted." => {
+            "Struktura lista je zaključana: listovi se ne mogu dodavati, premeštati, preimenovati ni brisati."
+        }
+        "Lock the sheet structure so sheets can't be added, moved, renamed or deleted." => {
+            "Zaključaj strukturu listova tako da se ne mogu dodavati, premeštati, preimenovati ni brisati."
+        }
+        "Properties" => "Svojstva",
+        "Title" => "Naslov",
+        "Subject" => "Predmet",
+        "Author" => "Autor",
+        "Company" => "Kompanija",
+        "Keywords" => "Ključne reči",
+        "Description" => "Opis",
+        "No workbook is open." => "Nijedna radna sveska nije otvorena.",
+        "Save as type" => "Sačuvaj kao tip",
+        "Excel Workbook (*.xlsx)" => "Excel radna sveska (*.xlsx)",
+        "CSV UTF-8 (Comma delimited) (*.csv)" => "CSV UTF-8 (odvojeno zapetama) (*.csv)",
+        "Web Page (*.html)" => "Veb stranica (*.html)",
+        "PDF (*.pdf)" => "PDF (*.pdf)",
+        "Download" => "Preuzmi",
+        "A CSV file, web page or PDF is a copy: the workbook keeps its own file." => {
+            "CSV fajl, veb stranica ili PDF su kopija: radna sveska zadržava svoj fajl."
+        }
+        "Save the workbook under another name or in another folder." => "Sačuvaj radnu svesku pod drugim imenom ili u drugoj fascikli.",
+        "Print Active Sheets" => "Štampaj aktivne listove",
+        "Print Entire Workbook" => "Štampaj celu radnu svesku",
+        "Fit Sheet on One Page" => "Uklopi list na jednu stranicu",
+        "Page Setup…" => "Podešavanje stranice…",
+        "Page {page} of {pages}" => "Stranica {page} od {pages}",
+        "Nothing to print." => "Nema ničega za štampu.",
+        "Previous page" => "Prethodna stranica",
+        "Next page" => "Sledeća stranica",
+        "Create PDF" => "Napravi PDF",
+        "Save the sheet as a PDF document that keeps its page layout." => "Sačuvaj list kao PDF dokument koji zadržava izgled stranice.",
+        "Change File Type" => "Promeni tip fajla",
+        "CSV (Comma delimited)" => "CSV (odvojeno zapetama)",
+        "Save the active sheet as comma-separated text." => "Sačuvaj aktivni list kao tekst odvojen zapetama.",
+        "Web Page (.html)" => "Veb stranica (.html)",
+        "Save the workbook as a web page." => "Sačuvaj radnu svesku kao veb stranicu.",
+        "Options|General" => "Opcije|Opšte",
+        "Options|Save" => "Opcije|Sačuvaj",
+        "Show formula bar" => "Prikaži traku formule",
+        "Save .xlsx workbooks automatically after every change" => "Automatski sačuvaj .xlsx radne sveske posle svake izmene",
+        "Workbook calculation" => "Izračunavanje radne sveske",
+        "Enable iterative calculation" => "Omogući iterativno izračunavanje",
+        "Calculation settings are saved with the workbook." => "Podešavanja izračunavanja se čuvaju sa radnom sveskom.",
+        _ => return None,
+    })
+}
diff --git a/crates/ui-egui/src/i18n/zh.rs b/crates/ui-egui/src/i18n/zh.rs
index d1cf704..a9989f2 100644
--- a/crates/ui-egui/src/i18n/zh.rs
+++ b/crates/ui-egui/src/i18n/zh.rs
@@ -121,6 +121,12 @@ pub(super) fn translate(text: &str) -> Option<&'static str> {
         "Select\nObjects" => "选择\n对象",
         "Themes" => "主题",
         "Margins" => "页边距",
+        "Left Margin" => "左边距",
+        "Right Margin" => "右边距",
+        "Top Margin" => "上边距",
+        "Bottom Margin" => "下边距",
+        "Header Margin" => "页眉边距",
+        "Footer Margin" => "页脚边距",
         "Size" => "纸张大小",
         "Print\nArea" => "打印\n区域",
         "Set Print Area" => "设置打印区域",
diff --git a/crates/ui-egui/src/icons.rs b/crates/ui-egui/src/icons.rs
index fe9f7bf..3e5cdf3 100644
--- a/crates/ui-egui/src/icons.rs
+++ b/crates/ui-egui/src/icons.rs
@@ -113,6 +113,8 @@ pub enum Icon {
     /// Light/dark appearance: a circle, its right half filled.
     Appearance,
     Sheet,
+    /// All Sheets navigator next to the sheet tabs: a list of rows with a bullet each.
+    SheetList,
     Book,
     Folder,
     /// Header & Footer: a page with its top / bottom band marked.
@@ -419,6 +421,12 @@ pub fn paint(p: &Painter, rect: Rect, icon: Icon, c: Color32) {
             g.line(&[(2.0, 8.0), (8.0, 2.5), (14.0, 8.0)], c, 1.2);
             g.line(&[(4.0, 6.5), (4.0, 13.5), (12.0, 13.5), (12.0, 6.5)], c, 1.2);
         }
+        Icon::SheetList => {
+            for y in [4.0, 8.0, 12.0] {
+                g.rect(2.5, y - 1.0, 2.0, 2.0, Some(c), None);
+                g.stroke(&[(6.5, y), (13.5, y)], c);
+            }
+        }
         Icon::More => {
             for x in [4.0, 8.0, 12.0] {
                 g.circle(x, 8.0, 1.0, Some(c), None);
diff --git a/crates/ui-egui/src/keymap.rs b/crates/ui-egui/src/keymap.rs
index 21bf41f..cb4f7c6 100644
--- a/crates/ui-egui/src/keymap.rs
+++ b/crates/ui-egui/src/keymap.rs
@@ -179,12 +179,14 @@ pub(crate) fn dispatch(app: &mut SheetApp, ctx: &egui::Context, key: Key, physic
         }
         Shortcut::Dialog(name, params) => app.open_dialog(name, params),
         Shortcut::Date | Shortcut::Time => {
-            let now = gridcraft_engine::calc::now_serial();
-            let (value, format) = if shortcut == Shortcut::Date { (now.floor(), "m/d/yyyy") } else { (now.fract(), "h:mm AM/PM") };
             let text = app
                 .session
                 .active()
-                .map(|d| gridcraft_engine::display::format(&gridcraft_engine::core::Value::Number(value), format, &d.wb).text)
+                .map(|d| {
+                    let now = gridcraft_engine::core::date::serial_in_system(d.wb.date_system, gridcraft_engine::calc::now_serial());
+                    let (value, format) = if shortcut == Shortcut::Date { (now.floor(), "m/d/yyyy") } else { (now.fract(), "h:mm AM/PM") };
+                    gridcraft_engine::display::format(&gridcraft_engine::core::Value::Number(value), format, &d.wb).text
+                })
                 .unwrap_or_default();
             edit_with(app, text);
         }
@@ -212,12 +214,16 @@ pub(crate) fn dispatch(app: &mut SheetApp, ctx: &egui::Context, key: Key, physic
             let dc = if shortcut == Shortcut::ScreenRight { cols } else { -cols };
             let _ = app.session.run("selection.move", json!({"dr": 0, "dc": dc, "extend": m.shift}));
             app.grid.ensure_visible = true;
+            app.grid.reveal_moving_end = m.shift;
         }
         Shortcut::Edit => app.begin_edit(None, false),
         Shortcut::ContextMenu => app.grid.context_menu = Some(geo.cell_rect(sh, active).center()),
         Shortcut::DropDown => {
             if sh.validations.iter().any(|d| d.in_cell_dropdown && d.ranges.iter().any(|r| r.contains(active))) {
                 app.grid.list_picker = Some(active);
+            } else if sh.has_filter_button(active) {
+                let at = geo.mirror_pos(crate::grid::filter_button_rect(geo, sh, active).center());
+                app.grid.filter_menu = Some((active.col, at));
             }
         }
         Shortcut::Zoom(step) => {
@@ -243,4 +249,5 @@ fn extend(app: &mut SheetApp, anchor: CellRef, active: CellRef, to: CellRef) {
         d.selection.anchor = anchor;
     }
     app.grid.ensure_visible = true;
+    app.grid.reveal_moving_end = true;
 }
diff --git a/crates/ui-egui/src/keytips/keytip_table.rs b/crates/ui-egui/src/keytips/keytip_table.rs
index 9e2735f..5415b9d 100644
--- a/crates/ui-egui/src/keytips/keytip_table.rs
+++ b/crates/ui-egui/src/keytips/keytip_table.rs
@@ -200,7 +200,7 @@ mod tests {
     #[test]
     fn item_letter_is_one_level_deep() {
         assert_eq!(item_letter("HV", "dialog:pasteSpecial"), Some("HVS"));
-        assert_eq!(item_letter("HV", "edit.pasteSpecial"), Some("HVP"));
+        assert_eq!(item_letter("HV", "edit.paste"), Some("HVP"));
         assert_eq!(item_letter("H", "dialog:pasteSpecial"), None, "the item badge waits for its group letter");
         assert_eq!(item_letter("HO", "home.autofitColumnWidth"), Some("HOI"));
     }
diff --git a/crates/ui-egui/src/keytips/keytip_table/generated.rs b/crates/ui-egui/src/keytips/keytip_table/generated.rs
index 143c157..79920b5 100644
--- a/crates/ui-egui/src/keytips/keytip_table/generated.rs
+++ b/crates/ui-egui/src/keytips/keytip_table/generated.rs
@@ -147,7 +147,7 @@ pub const SEQUENCES: &[(&str, Entry)] = &[
     ("HUI", Entry::Finish(Action::Command("formulas.autoSum"))), // Excel: Auto Min; AutoSum: Min (variant TBD)
     ("HUM", Entry::Finish(Action::Command("formulas.autoSum"))), // Excel: Auto Max; AutoSum: Max (variant TBD)
     ("HV", Entry::Continue),  // Excel: Paste; group level:
-    ("HVP", Entry::Finish(Action::Command("edit.pasteSpecial"))), // Excel: Paste
+    ("HVP", Entry::Finish(Action::Command("edit.paste"))), // Excel: Paste
     ("HW", Entry::Continue),  // Excel: Wrap Text Menu; group level: containment(Wrap Text)
     ("HWW", Entry::Finish(Action::Command("home.wrapText"))), // Excel: Wrap Text
     ("HX", Entry::Finish(Action::Command("edit.cut"))), // Excel: Cut
diff --git a/crates/ui-egui/src/keytips/keytips.json b/crates/ui-egui/src/keytips/keytips.json
index cbb8e04..59aeadc 100644
--- a/crates/ui-egui/src/keytips/keytips.json
+++ b/crates/ui-egui/src/keytips/keytips.json
@@ -958,7 +958,7 @@
   {
    "seq": "HVP",
    "kind": "command",
-   "target": "edit.pasteSpecial",
+   "target": "edit.paste",
    "excel": "Paste",
    "note": ""
   },
diff --git a/crates/ui-egui/src/lib.rs b/crates/ui-egui/src/lib.rs
index 0b19b25..be03199 100644
--- a/crates/ui-egui/src/lib.rs
+++ b/crates/ui-egui/src/lib.rs
@@ -179,6 +179,10 @@ pub struct Services {
     /// source spreadsheet recorded as numbers stay numbers ("Rp10,000.00" → 10000). `None` from
     /// the host pastes the plain text alone.
     pub paste_html: Option<Box<dyn FnMut() -> Option<String>>>,
+    /// Read the system clipboard's plain text for the ribbon and menu Paste commands (Cmd/Ctrl+V
+    /// gets it from egui's `Event::Paste`). `None` from the host, or no service (web), pastes
+    /// GridCraft's own clipboard.
+    pub paste_text: Option<Box<dyn FnMut() -> Option<String>>>,
     /// Web: deliver a file to the user (name, bytes).
     pub download: Option<Box<dyn Fn(&str, &[u8])>>,
     /// Web: start an asynchronous file pick; the bytes arrive later in `inbox`.
@@ -246,6 +250,14 @@ pub struct SheetApp {
     pub(crate) shots: control::Shots,
     /// Chart selected on the sheet (id).
     pub selected_chart: Option<u32>,
+    /// The system clipboard's text when GridCraft last copied without publishing to it (a
+    /// control-channel or MCP `edit.copy`/`edit.cut`). While the system clipboard still holds this
+    /// text, GridCraft's copy is the newer one and Paste uses it.
+    clipboard_text_at_copy: Option<String>,
+    /// The system clipboard's text right after GridCraft's last cut (the published text, or the
+    /// text noted for an unpublished cut); `None` after a copy, or once the clipboard is seen
+    /// holding other text. Once the cut has been pasted, Paste leaves this text alone.
+    cut_text: Option<String>,
     pub started: f64,
 }
 
@@ -287,6 +299,8 @@ impl SheetApp {
             keytips: keytips::KeyTips::default(),
             shots: control::Shots::default(),
             selected_chart: None,
+            clipboard_text_at_copy: None,
+            cut_text: None,
             started: now_ms(),
         }
     }
@@ -322,6 +336,17 @@ impl SheetApp {
 
     /// Runs an engine command (or a UI command) and handles UI requests it makes.
     pub fn run(&mut self, id: &str, params: Json) -> Result<Json, String> {
+        let r = self.run_command(id, params);
+        // This copy leaves the system clipboard alone: note what it holds, so Paste can tell
+        // that GridCraft's copy is newer while that text is still there.
+        if matches!(id, "edit.copy" | "edit.cut") && r.is_ok() {
+            self.clipboard_text_at_copy = self.system_clipboard_text();
+            self.cut_text = if id == "edit.cut" { self.clipboard_text_at_copy.clone() } else { None };
+        }
+        r
+    }
+
+    fn run_command(&mut self, id: &str, params: Json) -> Result<Json, String> {
         if matches!(id, "file.save" | "file.saveAs" | "file.saveBytes") {
             self.store_view_state();
         }
@@ -353,6 +378,13 @@ impl SheetApp {
         }
         let r = self.session.run(id, params);
         self.after_engine();
+        // The new chart is selected, as after inserting any object, so Delete removes it, not its data.
+        if id == "insert.chart"
+            && let Ok(r) = &r
+            && let Some(chart) = r.get("chart").and_then(Json::as_u64).and_then(|id| u32::try_from(id).ok())
+        {
+            self.selected_chart = Some(chart);
+        }
         if id == "file.exportPdf"
             && let Ok(r) = &r
         {
@@ -365,11 +397,14 @@ impl SheetApp {
     /// their existing internal clipboard behavior and do not write to the host clipboard.
     pub fn copy_to_clipboard(&mut self, ctx: &egui::Context, command: &str) {
         // Only ask the engine for HTML when the host can publish it.
-        let result = match self.run(command, json!({"html": self.services.copy_html.is_some()})) {
+        let result = match self.run_command(command, json!({"html": self.services.copy_html.is_some()})) {
             Ok(result) => result,
             Err(e) => return self.alert(e),
         };
         let Some(text) = result.get("text").and_then(Json::as_str) else { return };
+        // The system clipboard gets this copy, so its text decides what Paste pastes.
+        self.clipboard_text_at_copy = None;
+        self.cut_text = (command == "edit.cut").then(|| text.replace("\r\n", "\n"));
         if let Some(html) = result.get("html").and_then(Json::as_str)
             && let Some(copy_html) = &mut self.services.copy_html
         {
@@ -381,9 +416,21 @@ impl SheetApp {
         ctx.copy_text(text.to_string());
     }
 
-    /// Paste text that came from the system clipboard, with the clipboard's HTML flavour when the
-    /// host can read it.
+    /// Paste text that came from the system clipboard (Cmd/Ctrl+V, or the ribbon and menu Paste),
+    /// with the clipboard's HTML flavour when the host can read it.
+    ///
+    /// Excel pastes a cut once: after GridCraft's cut has been pasted, the system clipboard text
+    /// that came with it is not pasted again over the moved block; GridCraft's own (empty)
+    /// clipboard is pasted instead, which reports "Nothing to paste.". Other text means the
+    /// clipboard has moved on, so the cut's text is forgotten and pastes normally later.
     pub fn paste_external(&mut self, text: String) {
+        if Self::same_clipboard_text(Some(&text), self.cut_text.as_deref()) {
+            if self.session.clipboard.is_none() {
+                return self.run_or_alert("edit.paste", json!({}));
+            }
+        } else {
+            self.cut_text = None;
+        }
         let html = self.services.paste_html.as_mut().and_then(|read| read());
         let params = match html {
             Some(html) => json!({"text": text, "html": html}),
@@ -392,6 +439,34 @@ impl SheetApp {
         self.run_or_alert("edit.paste", params);
     }
 
+    /// Ribbon and menu Paste: paste the text on the system clipboard, as Cmd/Ctrl+V does. With no
+    /// text there, no host clipboard (web), or the text that was there when GridCraft last copied
+    /// without publishing, GridCraft's own clipboard is pasted.
+    pub fn paste_from_clipboard(&mut self) {
+        match self.system_clipboard_text() {
+            Some(text) if self.session.clipboard.is_none() || self.clipboard_text_at_copy.as_ref() != Some(&text) => self.paste_external(text),
+            _ => self.run_or_alert("edit.paste", json!({})),
+        }
+    }
+
+    /// The system clipboard's plain text, with the line endings of egui's `Event::Paste` text.
+    /// `None` when it holds no text or the host can't read it.
+    fn system_clipboard_text(&mut self) -> Option<String> {
+        self.services.paste_text.as_mut().and_then(|read| read()).filter(|t| !t.is_empty()).map(|t| t.replace("\r\n", "\n"))
+    }
+
+    /// Whether two clipboard texts are the same copy: trailing line breaks don't count, as in the
+    /// engine's `edit.paste`, and CRLF matches LF (egui's `Event::Paste` text may keep the host's).
+    fn same_clipboard_text(a: Option<&str>, b: Option<&str>) -> bool {
+        fn chars(t: &str) -> impl Iterator<Item = char> + '_ {
+            t.trim_end_matches(['\r', '\n']).chars().filter(|c| *c != '\r')
+        }
+        match (a, b) {
+            (Some(a), Some(b)) => chars(a).eq(chars(b)),
+            _ => false,
+        }
+    }
+
     /// Web: `file.exportPdf` without a path returns the PDF as base64; hand it to the browser as a download.
     fn deliver_pdf(&self, result: &Json) {
         if result.get("path").is_some() {
@@ -421,11 +496,39 @@ impl SheetApp {
             }
             return self.print_now(params);
         }
+        // Menu-style Export as PDF with no file named: ask where to save, like Save As does.
+        // Programmatic callers use `run` and keep getting the PDF bytes back.
+        if id == "file.exportPdf" && self.services.pick_save.is_some() && params.get("path").and_then(Json::as_str).is_none_or(str::is_empty) {
+            return self.export_pdf_with_picker(params);
+        }
         if let Err(e) = self.run(id, params) {
             self.alert(e);
         }
     }
 
+    /// Asks for a `.pdf` path with the save picker, then re-runs `file.exportPdf` with it. Other
+    /// params (range, sheets, fitToPage) are kept. A cancelled picker does nothing.
+    fn export_pdf_with_picker(&mut self, mut params: Json) {
+        if !self.commit_edit(0, 0, false, false) {
+            return;
+        }
+        let title = self.session.active().map(|d| d.display_title()).unwrap_or_else(|| "Book1".into());
+        let stem = std::path::Path::new(&title).file_stem().and_then(|s| s.to_str()).unwrap_or("Book1").to_string();
+        let Some(pick) = &self.services.pick_save else { return };
+        let Some(path) = pick(&format!("{stem}.pdf")) else { return };
+        // The picker may suggest a workbook extension; the export writes a PDF.
+        let path = std::path::Path::new(&path).with_extension("pdf").to_string_lossy().into_owned();
+        match &mut params {
+            Json::Object(map) => {
+                map.insert("path".into(), Json::String(path));
+            }
+            other => *other = json!({"path": path}),
+        }
+        if let Err(e) = self.run("file.exportPdf", params) {
+            self.alert(e);
+        }
+    }
+
     /// Shows a command error: a toast for an unavailable command, else a message box.
     fn alert(&mut self, e: String) {
         if e.contains("is not available right now") {
@@ -1079,6 +1182,8 @@ impl SheetApp {
                     self.run_or_alert("ui.ribbonTab", json!({"tab": tab}));
                     self.ui.ribbon_collapsed = false;
                 }
+                keytips::Action::Command(id @ ("edit.copy" | "edit.cut")) => self.copy_to_clipboard(ctx, id),
+                keytips::Action::Command("edit.paste") => self.paste_from_clipboard(),
                 keytips::Action::Command(id) => self.run_or_alert(id, json!({})),
                 keytips::Action::Dialog(name) => self.open_dialog(name, json!({})),
                 // Reserved sequence: fires silently while its command is missing. When the
diff --git a/crates/ui-egui/src/outline.rs b/crates/ui-egui/src/outline.rs
index 7eaf133..62e2cc3 100644
--- a/crates/ui-egui/src/outline.rs
+++ b/crates/ui-egui/src/outline.rs
@@ -142,6 +142,13 @@ impl Dir<'_> {
         let (a0, a1) = (a.max(top), (a + size).min(self.hi));
         (size > 0.0 && a1 > a0).then_some((a0, a1))
     }
+    /// The first on-screen line in `start..=end`: the frozen ones first, then the scrolling ones from the line
+    /// at the pane's edge, so a long group is not scanned from its far-off start.
+    fn first_visible(&self, start: u32, end: u32) -> Option<(u32, (f32, f32))> {
+        let at = if self.rows { self.geo.row_at(self.sh, self.split) } else { self.geo.col_at(self.sh, self.split) };
+        let scrolled = start.max(self.frozen).max(at);
+        (start..self.frozen.min(end.saturating_add(1))).chain(scrolled..=end).find_map(|l| self.visible(l).map(|v| (l, v)))
+    }
     fn point(&self, along: f32, across: f32) -> Pos2 {
         if self.rows { pos2(across, along) } else { pos2(along, across) }
     }
@@ -198,7 +205,7 @@ pub fn layout(geo: &Geo, sh: &Sheet) -> Layout {
                 continue;
             }
             // The bracket, over the part of the detail that is on screen.
-            let first = (grp.start..=grp.end).take(4096).find_map(|l| dir.visible(l).map(|v| (l, v)));
+            let first = dir.first_visible(grp.start, grp.end);
             let Some((first_line, (a0, _))) = first else { continue };
             let a1 = match button {
                 Some(mid) => mid - side / 2.0,
@@ -298,6 +305,28 @@ mod tests {
         assert_eq!(g.head_left(), g.rect.left());
     }
 
+    #[test]
+    fn long_groups_keep_their_bracket_past_4096_lines() {
+        for rows in [true, false] {
+            let mut sh = Sheet::new("S");
+            let map = if rows { &mut sh.rows } else { &mut sh.cols };
+            for i in 0..5000u32 {
+                map.entry(i).or_default().outline = 1;
+            }
+            for line in [0u32, 4095, 4096, 4200, 4970] {
+                let scroll = if rows { vec2(0.0, sh.row_top(line) as f32) } else { vec2(sh.col_left(line) as f32, 0.0) };
+                let g = Geo::new(&sh, Rect::from_min_size(pos2(0.0, 0.0), vec2(800.0, 600.0)), scroll);
+                let l = layout(&g, &sh);
+                assert_eq!(l.brackets.len(), 1, "rows={rows} line={line}");
+                assert_eq!(l.brackets[0].tick.is_some(), line == 0, "rows={rows} line={line}");
+            }
+            // Past the group's summary line nothing is left to bracket.
+            let scroll = if rows { vec2(0.0, sh.row_top(5100) as f32) } else { vec2(sh.col_left(5100) as f32, 0.0) };
+            let g = Geo::new(&sh, Rect::from_min_size(pos2(0.0, 0.0), vec2(800.0, 600.0)), scroll);
+            assert!(layout(&g, &sh).brackets.is_empty(), "rows={rows}");
+        }
+    }
+
     #[test]
     fn bands_push_the_headers_and_cells_in() {
         let sh = sheet();
diff --git a/crates/ui-egui/src/panes.rs b/crates/ui-egui/src/panes.rs
index 3100cfe..aaa9bec 100644
--- a/crates/ui-egui/src/panes.rs
+++ b/crates/ui-egui/src/panes.rs
@@ -17,7 +17,10 @@ pub fn show(app: &mut SheetApp, ui: &mut Ui) {
     }
     let Some(pane) = app.grid.pane.clone().or_else(|| app.session.comments_pane.then(|| "comments".to_string())) else { return };
     let t = Tokens::get(ui.ctx());
-    egui::Panel::right("task_pane").default_size(300.0).resizable(true).frame(egui::Frame::NONE.fill(t.ribbon).inner_margin(10)).show(ui, |ui| {
+    // Capped at half the window so a pane can never cover the sheet, whatever its content asks for.
+    let max = (ui.available_width() / 2.0).max(300.0);
+    let panel = egui::Panel::right("task_pane").default_size(300.0).max_size(max).resizable(true);
+    panel.frame(egui::Frame::NONE.fill(t.ribbon).inner_margin(10)).show(ui, |ui| {
         ui.horizontal(|ui| {
             let title = match pane.as_str() {
                 "comments" => "Comments",
@@ -62,7 +65,7 @@ fn comments(app: &mut SheetApp, ui: &mut Ui) {
             .stroke(egui::Stroke::new(1.0, Color32::from_gray(215)))
             .show(ui, |ui| {
                 ui.set_width(ui.available_width());
-                ui.horizontal(|ui| {
+                ui.horizontal_wrapped(|ui| {
                     if ui.link(egui::RichText::new(&cell).strong()).clicked() {
                         let _ = app.run("selection.set", json!({"cell": cell}));
                         app.grid.ensure_visible = true;
@@ -78,18 +81,23 @@ fn comments(app: &mut SheetApp, ui: &mut Ui) {
                 }
                 let key = egui::Id::new(("reply", &cell));
                 let mut draft: String = ui.ctx().data_mut(|m| m.get_temp(key)).unwrap_or_default();
+                // Buttons first, right to left, so the reply field gets exactly the width they leave:
+                // a field sized by a guess wider than the row pushes the resizable pane wider every frame.
                 ui.horizontal(|ui| {
-                    let r = ui.add(egui::TextEdit::singleline(&mut draft).hint_text("Reply…").desired_width(ui.available_width() - 120.0));
-                    if (r.lost_focus() && ui.input(|i| i.key_pressed(egui::Key::Enter)) || ui.small_button("Send").clicked()) && !draft.is_empty() {
-                        app.run_or_alert("review.replyComment", json!({"cell": cell, "text": draft}));
-                        draft.clear();
-                    }
-                    if ui.small_button(if c.resolved { "Reopen" } else { "Resolve" }).clicked() {
-                        app.run_or_alert("review.resolveComment", json!({"cell": cell, "resolved": !c.resolved}));
-                    }
-                    if ui.small_button("Delete").clicked() {
-                        app.run_or_alert("review.deleteComment", json!({"cell": cell}));
-                    }
+                    ui.with_layout(egui::Layout::right_to_left(egui::Align::Center), |ui| {
+                        if ui.small_button("Delete").clicked() {
+                            app.run_or_alert("review.deleteComment", json!({"cell": cell}));
+                        }
+                        if ui.small_button(if c.resolved { "Reopen" } else { "Resolve" }).clicked() {
+                            app.run_or_alert("review.resolveComment", json!({"cell": cell, "resolved": !c.resolved}));
+                        }
+                        let send = ui.small_button("Send").clicked();
+                        let r = ui.add(egui::TextEdit::singleline(&mut draft).hint_text("Reply…").desired_width(ui.available_width()));
+                        if (r.lost_focus() && ui.input(|i| i.key_pressed(egui::Key::Enter)) || send) && !draft.is_empty() {
+                            app.run_or_alert("review.replyComment", json!({"cell": cell, "text": draft}));
+                            draft.clear();
+                        }
+                    });
                 });
                 ui.ctx().data_mut(|m| m.insert_temp(key, draft));
             });
diff --git a/crates/ui-egui/src/paper_view.rs b/crates/ui-egui/src/paper_view.rs
index 110193a..621a979 100644
--- a/crates/ui-egui/src/paper_view.rs
+++ b/crates/ui-egui/src/paper_view.rs
@@ -284,6 +284,7 @@ pub(crate) fn interact(app: &mut SheetApp, ui: &mut egui::Ui, resp: &egui::Respo
         commit(app);
     }
     let Some(pg) = geo.paper.clone() else { return };
+    ruler_margins(app, ui, geo, &pg, sh, wb.active_sheet);
     if std::mem::take(&mut app.grid.hf_start) {
         begin(app, wb.active_sheet, sh, (pg.data_rows.0, pg.data_cols.0), HfZone { footer: false, section: 1 });
     }
@@ -510,6 +511,14 @@ fn editor(app: &mut SheetApp, ui: &mut egui::Ui, geo: &Geo, pg: &PageGrid) {
     app.grid.hf_edit = Some(e);
 }
 
+/// Screen rectangles of the horizontal and vertical rulers. Right-to-left sheets mirror both:
+/// the vertical ruler sits on the right, beside the row headings.
+fn ruler_rects(outer: Rect, geo: &Geo) -> (Rect, Rect) {
+    let hr = geo.mirror_rect(Rect::from_min_max(pos2(geo.cells.left(), outer.top()), pos2(geo.cells.right(), outer.top() + RULER)));
+    let (x0, x1) = if geo.rtl { (outer.right() - RULER, outer.right()) } else { (outer.left(), outer.left() + RULER) };
+    (hr, Rect::from_min_max(pos2(x0, geo.cells.top()), pos2(x1, geo.cells.bottom())))
+}
+
 /// Horizontal and vertical rulers (`outer` is the grid area including the rulers).
 pub(crate) fn paint_rulers(app: &SheetApp, p: &Painter, outer: Rect, geo: &Geo, t: &Tokens) {
     let Some(pg) = geo.paper.clone() else { return };
@@ -523,17 +532,20 @@ pub(crate) fn paint_rulers(app: &SheetApp, p: &Painter, outer: Rect, geo: &Geo,
     let minor = if metric { 2.0 } else { 4.0 };
     let label_every = ((22.0 / unit).ceil() as usize).max(1);
     let font = theme::ui_font(9.5);
-    let hr = Rect::from_min_max(pos2(geo.cells.left(), outer.top()), pos2(geo.cells.right(), outer.top() + RULER));
-    let vr = Rect::from_min_max(pos2(outer.left(), geo.cells.top()), pos2(outer.left() + RULER, geo.cells.bottom()));
+    let (hr, vr) = ruler_rects(outer, geo);
+    // Right-to-left sheets: the horizontal ruler is mirrored with the pages (ticks run from the
+    // right margin leftwards).
+    let mx = |x: f32| geo.mirror_x(x);
     p.rect_filled(Rect::from_min_max(outer.min, pos2(outer.right(), outer.top() + RULER)), 0.0, t.window);
-    p.rect_filled(Rect::from_min_max(outer.min, pos2(outer.left() + RULER, outer.bottom())), 0.0, t.window);
+    p.rect_filled(Rect::from_min_max(pos2(vr.left(), outer.top()), pos2(vr.right(), outer.bottom())), 0.0, t.window);
     let ((i0, i1), (j0, j1)) = visible_pages(geo, &pg);
-    let [ml, mr, mt, mb, ..] = pg.margins;
+    let [ml, mr, mt, mb, mh, mf] = pg.margins;
     // One ruler span per page: margins shaded, the printable part light, ticks from the margin.
     let span = |p: &Painter, from: f32, to: f32, m0: f32, m1: f32, horizontal: bool, area: Rect| {
         let band = |a: f32, b: f32| {
             if horizontal {
-                Rect::from_min_max(pos2(a, area.top() + 2.0), pos2(b, area.bottom() - 2.0))
+                let (a, b) = (mx(a), mx(b));
+                Rect::from_min_max(pos2(a.min(b), area.top() + 2.0), pos2(a.max(b), area.bottom() - 2.0))
             } else {
                 Rect::from_min_max(pos2(area.left() + 2.0, a), pos2(area.right() - 2.0, b))
             }
@@ -550,6 +562,7 @@ pub(crate) fn paint_rulers(app: &SheetApp, p: &Painter, outer: Rect, geo: &Geo,
             if pos > m1 + 0.5 {
                 break;
             }
+            let pos = if horizontal { mx(pos) } else { pos };
             let major = s.is_multiple_of(minor as usize);
             let len = if major {
                 6.0
@@ -569,6 +582,8 @@ pub(crate) fn paint_rulers(app: &SheetApp, p: &Painter, outer: Rect, geo: &Geo,
             }
             let (a, b) = if horizontal {
                 (pos2(pos, area.bottom() - 2.0 - len), pos2(pos, area.bottom() - 2.0))
+            } else if geo.rtl {
+                (pos2(area.left() + 2.0, pos), pos2(area.left() + 2.0 + len, pos))
             } else {
                 (pos2(area.right() - 2.0 - len, pos), pos2(area.right() - 2.0, pos))
             };
@@ -586,14 +601,246 @@ pub(crate) fn paint_rulers(app: &SheetApp, p: &Painter, outer: Rect, geo: &Geo,
         let a = screen(geo, 0.0, y).y;
         let b = screen(geo, 0.0, y + h).y;
         span(p, a, b, screen(geo, 0.0, y + mt).y, screen(geo, 0.0, y + h - mb).y, false, vr);
+        // Header and footer margins: a small marker at each distance, grabbable like the margins.
+        let pc = p.with_clip_rect(vr);
+        for at in [screen(geo, 0.0, y + mh).y, screen(geo, 0.0, y + h - mf).y] {
+            let (x, d) = if geo.rtl { (vr.right() - 2.0, -6.0) } else { (vr.left() + 2.0, 6.0) };
+            pc.add(egui::Shape::convex_polygon(vec![pos2(x, at - 3.5), pos2(x, at + 3.5), pos2(x + d, at)], t.header_text, Stroke::NONE));
+        }
     }
     p.line_segment([pos2(outer.left(), outer.top() + RULER - 0.5), pos2(outer.right(), outer.top() + RULER - 0.5)], Stroke::new(1.0, t.header_line));
     p.line_segment(
-        [pos2(outer.left() + RULER - 0.5, outer.top()), pos2(outer.left() + RULER - 0.5, outer.bottom())],
+        if geo.rtl {
+            [pos2(vr.left() + 0.5, outer.top()), pos2(vr.left() + 0.5, outer.bottom())]
+        } else {
+            [pos2(vr.right() - 0.5, outer.top()), pos2(vr.right() - 0.5, outer.bottom())]
+        },
         Stroke::new(1.0, t.header_line),
     );
 }
 
+/// A page edge that can be dragged on a ruler.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Edge {
+    Left,
+    Right,
+    Top,
+    Bottom,
+    /// Distance of the header from the top of the page.
+    Header,
+    /// Distance of the footer from the bottom of the page.
+    Footer,
+}
+
+impl Edge {
+    /// Index into `PrintSettings::margins` / `PageGrid::margins`.
+    fn index(self) -> usize {
+        match self {
+            Edge::Left => 0,
+            Edge::Right => 1,
+            Edge::Top => 2,
+            Edge::Bottom => 3,
+            Edge::Header => 4,
+            Edge::Footer => 5,
+        }
+    }
+    /// The `pageLayout.pageSetup` margin key.
+    fn key(self) -> &'static str {
+        ["left", "right", "top", "bottom", "header", "footer"][self.index()]
+    }
+    fn label(self) -> &'static str {
+        ["Left Margin", "Right Margin", "Top Margin", "Bottom Margin", "Header Margin", "Footer Margin"][self.index()]
+    }
+    fn horizontal(self) -> bool {
+        matches!(self, Edge::Left | Edge::Right)
+    }
+}
+
+/// A margin being dragged on a ruler: the page it started on and the previewed value (inches).
+#[derive(Clone, Debug)]
+pub struct RulerDrag {
+    pub sheet: usize,
+    pub edge: Edge,
+    /// Page column (horizontal ruler) or row (vertical ruler) the drag started on.
+    pub page: usize,
+    pub start_inches: f32,
+    pub inches: f32,
+    /// The sheet re-paginated with `inches` (page breaks and fit-to-page scale as a commit would
+    /// give them), rebuilt when the value changes.
+    preview: Option<(f32, Arc<PageGrid>)>,
+}
+
+/// Content that must stay between the margins, in points.
+const MIN_CONTENT_PT: f64 = 36.0;
+/// Screen distance within which a ruler margin edge is grabbed.
+const EDGE_GRAB: f32 = 4.0;
+
+/// Margin (inches, rounded to 0.01) for an edge dragged to `rel_pt` points from the page's
+/// left/top edge. The margin stays on the page and leaves [`MIN_CONTENT_PT`] between the two
+/// margins of its axis. `None` for NaN/infinite input or a page without a size.
+pub fn margin_from_drag(edge: Edge, rel_pt: f64, page_pt: (f32, f32), margins_in: [f32; 6]) -> Option<f32> {
+    let page = f64::from(if edge.horizontal() { page_pt.0 } else { page_pt.1 });
+    if !rel_pt.is_finite() || !page.is_finite() || page <= 0.0 {
+        return None;
+    }
+    let other = f64::from(margins_in.get(edge.index() ^ 1).copied().filter(|v| v.is_finite())?).max(0.0) * 72.0;
+    let raw = match edge {
+        Edge::Left | Edge::Top | Edge::Header => rel_pt,
+        Edge::Right | Edge::Bottom | Edge::Footer => page - rel_pt,
+    };
+    let mut max = (page - other - MIN_CONTENT_PT).max(0.0);
+    let mut min = 0.0_f64;
+    let pt_of = |i: usize| f64::from(margins_in.get(i).copied().filter(|v| v.is_finite()).unwrap_or(0.0)).max(0.0) * 72.0;
+    match edge {
+        // The header/footer sits within its page margin (conservative: never past the margin edge).
+        Edge::Header => max = max.min(pt_of(2)),
+        Edge::Footer => max = max.min(pt_of(3)),
+        // ... so the top/bottom margin can't be dragged inside it.
+        Edge::Top => min = pt_of(4),
+        Edge::Bottom => min = pt_of(5),
+        _ => {}
+    }
+    let pt = raw.clamp(min.min(max), max);
+    Some(((pt / 72.0 * 100.0).round() / 100.0) as f32)
+}
+
+/// The grid while a margin is dragged: the sheet is re-paginated with the previewed margin, so
+/// the content area, page breaks and the fit-to-page scale are those a commit would give.
+pub(crate) fn with_dragged_margin(app: &mut SheetApp, wb: &Workbook, si: usize, pg: Arc<PageGrid>) -> Arc<PageGrid> {
+    let Some(d) = app.grid.ruler_drag.as_mut().filter(|d| d.sheet == si) else { return pg };
+    if let Some((v, g)) = &d.preview
+        && (*v - d.inches).abs() < f32::EPSILON
+    {
+        return g.clone();
+    }
+    let mut w = wb.clone();
+    let Some(sheet) = w.sheets.get_mut(si) else { return pg };
+    let Some(slot) = Arc::make_mut(sheet).print.margins.get_mut(d.edge.index()) else { return pg };
+    *slot = d.inches;
+    let rows = pg.row_bands.last().map_or(0, |b| b.1);
+    let cols = pg.col_bands.last().map_or(0, |b| b.1);
+    let Some(g) = PageGrid::build(&w, si, rows, cols) else { return pg };
+    let g = Arc::new(g);
+    d.preview = Some((d.inches, g.clone()));
+    g
+}
+
+/// Points per layout unit of the grid (paper size over the layout page size).
+fn pt_per_unit(pg: &PageGrid) -> Option<f64> {
+    let k = f64::from(pg.paper_pt.0) / pg.page_w;
+    (k.is_finite() && k > 0.0).then_some(k)
+}
+
+/// The margin edge of a visible page under `pos` on the horizontal (`h`) or vertical ruler.
+fn edge_at(geo: &Geo, pg: &PageGrid, pos: Pos2, h: bool) -> Option<(Edge, usize)> {
+    let ((i0, i1), (j0, j1)) = visible_pages(geo, pg);
+    let [ml, mr, mt, mb, mh, mf] = pg.margins;
+    let mut best: Option<(f32, Edge, usize)> = None;
+    let mut consider = |d: f32, e: Edge, page: usize| {
+        if d <= EDGE_GRAB && best.is_none_or(|b| d < b.0) {
+            best = Some((d, e, page));
+        }
+    };
+    if h {
+        for j in j0..=j1.min(j0.saturating_add(200)) {
+            let (x, _, w, _) = pg.page_rect(0, j);
+            consider((screen(geo, x + ml, 0.0).x - pos.x).abs(), Edge::Left, j);
+            consider((screen(geo, x + w - mr, 0.0).x - pos.x).abs(), Edge::Right, j);
+        }
+    } else {
+        for i in i0..=i1.min(i0.saturating_add(200)) {
+            let (_, y, _, hh) = pg.page_rect(i, 0);
+            consider((screen(geo, 0.0, y + mt).y - pos.y).abs(), Edge::Top, i);
+            consider((screen(geo, 0.0, y + hh - mb).y - pos.y).abs(), Edge::Bottom, i);
+            consider((screen(geo, 0.0, y + mh).y - pos.y).abs(), Edge::Header, i);
+            consider((screen(geo, 0.0, y + hh - mf).y - pos.y).abs(), Edge::Footer, i);
+        }
+    }
+    best.map(|(_, e, p)| (e, p))
+}
+
+/// Dragging the margin edges on the rulers sets the page margins: a resize cursor and a tooltip
+/// on hover, a live preview while dragging, one `pageLayout.pageSetup` (one undo step) on
+/// release, Esc cancels.
+fn ruler_margins(app: &mut SheetApp, ui: &mut egui::Ui, geo: &Geo, pg: &PageGrid, sh: &Sheet, si: usize) {
+    let Some(outer) = app.grid.rect else { return };
+    if geo.rect.top() - outer.top() < RULER - 0.5 {
+        app.grid.ruler_drag = None;
+        return;
+    }
+    // Leaving the sheet or the view drops the drag.
+    if app.grid.ruler_drag.as_ref().is_some_and(|d| d.sheet != si) {
+        app.grid.ruler_drag = None;
+    }
+    let (hr, vr) = ruler_rects(outer, geo);
+    // Right-to-left sheets mirror the pages and the horizontal ruler; hit-testing is logical.
+    let hresp = ui.interact(hr, egui::Id::new("ruler_margin_h"), egui::Sense::drag());
+    let vresp = ui.interact(vr, egui::Id::new("ruler_margin_v"), egui::Sense::drag());
+    let margins_in = |sh: &Sheet| -> [f32; 6] {
+        let m = |i: usize| sh.print.margins.get(i).copied().unwrap_or(0.5);
+        [m(0), m(1), m(2), m(3), m(4), m(5)]
+    };
+    let current = margins_in(sh);
+    let metric = metric(app);
+    let tip = |ui: &egui::Ui, app: &SheetApp, edge: Edge, inches: f32| {
+        let value = if metric { format!("{:.2} cm", inches * 2.54) } else { format!("{inches:.2} in") };
+        let text = format!("{}: {value}", app.ui.language.tr(edge.label()));
+        egui::Tooltip::always_open(ui.ctx().clone(), ui.layer_id(), egui::Id::new("ruler_margin_tip"), egui::PopupAnchor::Pointer).show(|ui| {
+            ui.label(text);
+        });
+    };
+    let cursor = |ui: &egui::Ui, edge: Edge| {
+        ui.ctx().set_cursor_icon(if edge.horizontal() { egui::CursorIcon::ResizeHorizontal } else { egui::CursorIcon::ResizeVertical });
+    };
+    if let Some(d) = app.grid.ruler_drag.clone() {
+        if ui.input_mut(|i| i.consume_key(egui::Modifiers::NONE, Key::Escape)) {
+            app.grid.ruler_drag = None;
+            return;
+        }
+        cursor(ui, d.edge);
+        let down = ui.input(|i| i.pointer.primary_down());
+        let pos = ui.input(|i| i.pointer.latest_pos()).map(|p| geo.mirror_pos(p));
+        let mut cur = d.clone();
+        if let (Some(pos), Some(k)) = (pos, pt_per_unit(pg)) {
+            let rel = if d.edge.horizontal() {
+                let page_x = pg.page_x(d.page);
+                f64::from(geo.scroll.x) + f64::from((pos.x - geo.cells.left()) / geo.z) - page_x
+            } else {
+                let page_y = pg.page_y(d.page);
+                f64::from(geo.scroll.y) + f64::from((pos.y - geo.cells.top()) / geo.z) - page_y
+            };
+            if let Some(v) = margin_from_drag(d.edge, rel * k, pg.paper_pt, current) {
+                cur.inches = v;
+            }
+        }
+        if down {
+            tip(ui, app, cur.edge, cur.inches);
+            app.grid.ruler_drag = Some(cur);
+            ui.ctx().request_repaint();
+        } else {
+            app.grid.ruler_drag = None;
+            if (cur.inches - cur.start_inches).abs() > f32::EPSILON {
+                app.run_or_alert("pageLayout.pageSetup", json!({"sheet": si, "margins": {cur.edge.key(): cur.inches}}));
+            }
+        }
+        return;
+    }
+    for (resp, h) in [(&hresp, true), (&vresp, false)] {
+        let Some(pos) = resp.hover_pos().or_else(|| resp.interact_pointer_pos()) else { continue };
+        let origin = if resp.drag_started() { ui.input(|i| i.pointer.press_origin()).unwrap_or(pos) } else { pos };
+        let origin = geo.mirror_pos(origin);
+        let Some((edge, page)) = edge_at(geo, pg, origin, h) else { continue };
+        let value = current.get(edge.index()).copied().unwrap_or(0.5);
+        if resp.drag_started() {
+            app.grid.ruler_drag = Some(RulerDrag { sheet: si, edge, page, start_inches: value, inches: value, preview: None });
+            cursor(ui, edge);
+        } else if resp.hovered() {
+            cursor(ui, edge);
+            tip(ui, app, edge, value);
+        }
+    }
+}
+
 /// The Header & Footer contextual ribbon tab.
 pub fn ribbon_tab(app: &mut SheetApp, ui: &mut egui::Ui) {
     use crate::widgets::big_button;
@@ -667,3 +914,47 @@ fn sep(ui: &mut egui::Ui) {
     let (r, _) = ui.allocate_exact_size(vec2(13.0, 72.0), egui::Sense::hover());
     ui.painter().line_segment([pos2(r.center().x, r.top() + 6.0), pos2(r.center().x, r.bottom() - 6.0)], Stroke::new(1.0, t.separator));
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const A4: (f32, f32) = (595.0, 842.0);
+
+    #[test]
+    fn drag_maps_to_margins_and_clamps_inside_the_page() {
+        let m = [0.7, 0.7, 0.75, 0.75, 0.3, 0.3];
+        // 72 pt from the left edge is one inch; from the right edge the margin is measured inward.
+        assert_eq!(margin_from_drag(Edge::Left, 72.0, A4, m), Some(1.0));
+        assert_eq!(margin_from_drag(Edge::Right, f64::from(A4.0) - 36.0, A4, m), Some(0.5));
+        assert_eq!(margin_from_drag(Edge::Top, 108.0, A4, m), Some(1.5));
+        // Dragged off the page: never negative (top/bottom keep the header/footer distance).
+        assert_eq!(margin_from_drag(Edge::Left, -50.0, A4, m), Some(0.0));
+        assert_eq!(margin_from_drag(Edge::Bottom, f64::from(A4.1) + 99.0, A4, m), Some(0.3));
+        // Dragged across the opposite margin: stops a minimum content width short of it.
+        let max = margin_from_drag(Edge::Left, 10_000.0, A4, m).unwrap();
+        assert!((f64::from(max) * 72.0 - (f64::from(A4.0) - 0.7 * 72.0 - MIN_CONTENT_PT)).abs() < 1.0, "{max}");
+        // Hostile input is ignored, not clamped to something arbitrary.
+        assert_eq!(margin_from_drag(Edge::Left, f64::NAN, A4, m), None);
+        assert_eq!(margin_from_drag(Edge::Left, f64::INFINITY, A4, m), None);
+        assert_eq!(margin_from_drag(Edge::Left, 10.0, (0.0, 0.0), m), None);
+        assert_eq!(margin_from_drag(Edge::Left, 10.0, A4, [0.7, f32::NAN, 0.7, 0.7, 0.3, 0.3]), None);
+        // Oversized opposite margin leaves nothing to drag into.
+        assert_eq!(margin_from_drag(Edge::Left, 300.0, A4, [0.0, 40.0, 0.0, 0.0, 0.3, 0.3]), Some(0.0));
+        // Header/footer distances are measured from the top / bottom edge.
+        assert_eq!(margin_from_drag(Edge::Header, 36.0, A4, m), Some(0.5));
+        assert_eq!(margin_from_drag(Edge::Footer, f64::from(A4.1) - 18.0, A4, m), Some(0.25));
+        assert_eq!(margin_from_drag(Edge::Footer, 1e9, A4, m), Some(0.0));
+        // Header stays within the top margin (0.75 in), footer within the bottom margin.
+        assert_eq!(margin_from_drag(Edge::Header, 500.0, A4, m), Some(0.75));
+        assert_eq!(margin_from_drag(Edge::Footer, f64::from(A4.1) - 500.0, A4, m), Some(0.75));
+        // The top/bottom margin can't be dragged inside the header/footer distance (0.3 in).
+        assert_eq!(margin_from_drag(Edge::Top, 2.0, A4, m), Some(0.3));
+        assert_eq!(margin_from_drag(Edge::Bottom, f64::from(A4.1) - 2.0, A4, m), Some(0.3));
+        // Hostile header/footer values (NaN, negative, huge) never panic or escape the page.
+        assert_eq!(margin_from_drag(Edge::Header, 10.0, A4, [0.7, 0.7, 0.75, 0.75, f32::NAN, 0.3]), Some(0.14));
+        assert_eq!(margin_from_drag(Edge::Top, 300.0, A4, [0.7, 0.7, 0.75, 0.75, -5.0, f32::INFINITY]), Some(4.17));
+        assert_eq!(margin_from_drag(Edge::Header, f64::NAN, A4, m), None);
+        assert!(margin_from_drag(Edge::Footer, 10.0, A4, [0.0, 0.0, 1e9, 1e9, 0.3, 1e9]).is_some_and(|v| (0.0..=11.7).contains(&v)));
+    }
+}
diff --git a/crates/ui-egui/src/pivot_pane.rs b/crates/ui-egui/src/pivot_pane.rs
index 14d69db..0657026 100644
--- a/crates/ui-egui/src/pivot_pane.rs
+++ b/crates/ui-egui/src/pivot_pane.rs
@@ -64,13 +64,26 @@ pub fn show(app: &mut SheetApp, ui: &mut Ui) {
                 })
                 .unwrap_or_default()
         };
+        // Σ Values (two or more value fields) sits in Rows or Columns; it moves only between them.
+        const VALUES_FIELD: &str = "Σ Values";
+        let values_key = if info["valuesOnRows"].as_bool().unwrap_or(false) { "rows" } else { "columns" };
+        let values_at = info["valuesPosition"].as_u64().map(|p| p as usize);
+        let area_with_values = |key: &str| -> Vec<String> {
+            let mut v = area(key);
+            if key == values_key && area("values").len() > 1 {
+                let at = values_at.unwrap_or(v.len()).min(v.len());
+                v.insert(at, VALUES_FIELD.to_string());
+            }
+            v
+        };
         ui.columns(2, |cols| {
             for (i, (key, label)) in [("filters", "Filters"), ("columns", "Columns"), ("rows", "Rows"), ("values", "Values")].iter().enumerate() {
                 let ui = &mut cols[i % 2];
                 ui.label(egui::RichText::new(*label).strong());
                 egui::Frame::NONE.fill(t.window).corner_radius(4.0).inner_margin(4.0).show(ui, |ui| {
                     ui.set_min_size(vec2(ui.available_width(), 60.0));
-                    for f in area(key) {
+                    for f in area_with_values(key) {
+                        let is_values = f == VALUES_FIELD;
                         let b = ui.add(
                             egui::Button::new(egui::RichText::new(format!("{f} ▾")).font(theme::ui_font(12.0)))
                                 .fill(Color32::WHITE)
@@ -83,10 +96,13 @@ pub fn show(app: &mut SheetApp, ui: &mut Ui) {
                                 ("filters", "Move to Report Filter"),
                                 ("values", "Move to Values"),
                             ] {
-                                if to != *key && ui.button(l).clicked() {
+                                if to != *key && (!is_values || matches!(to, "rows" | "columns")) && ui.button(l).clicked() {
                                     app.run_or_alert("pivot.moveField", json!({"pivot": name, "field": f, "from": key, "to": to}));
                                 }
                             }
+                            if is_values {
+                                return;
+                            }
                             if *key == "values" {
                                 ui.separator();
                                 for (func, l) in [("sum", "Sum"), ("count", "Count"), ("average", "Average"), ("max", "Max"), ("min", "Min")] {
diff --git a/crates/ui-egui/src/ribbon.rs b/crates/ui-egui/src/ribbon.rs
index e8291ac..576e004 100644
--- a/crates/ui-egui/src/ribbon.rs
+++ b/crates/ui-egui/src/ribbon.rs
@@ -131,6 +131,9 @@ pub fn title_bar(app: &mut SheetApp, ui: &mut Ui) {
                 }
                 let share = small_button(ui, Icon::Share, "Share", "Share: export or save a copy", true);
                 egui::Popup::menu(&share).show(|ui| {
+                    if ui.button("Export as PDF…").clicked() {
+                        app.run_or_alert("file.exportPdf", json!({}));
+                    }
                     for (label, fmt) in
                         [("Save a Copy as Excel Workbook (.xlsx)…", "xlsx"), ("Export as CSV…", "csv"), ("Export as Web Page (.html)…", "html")]
                     {
@@ -343,6 +346,12 @@ fn anchor_keytip(app: &SheetApp, ui: &Ui, response: &egui::Response, targets: &[
     }
 }
 
+/// The `on` value for a ribbon checkbox command. A click has already flipped the checkbox bool, so
+/// it is sent as is; a key tip leaves the bool untouched, so the command gets the opposite.
+fn checkbox_on(clicked: bool, shown: bool) -> bool {
+    shown == clicked
+}
+
 /// Consume a one-shot keytip request for control `id` (set by `Action::Control`).
 fn invoke(app: &mut SheetApp, id: &str) -> bool {
     if app.ui.keytip_invoke == Some(id) {
@@ -367,7 +376,7 @@ struct ComboState {
 }
 
 /// What the user did with an [`editable_combo`].
-enum ComboResult {
+pub(crate) enum ComboResult {
     None,
     /// A row was applied: clicked or Enter on the highlighted row.
     Picked(String),
@@ -378,7 +387,7 @@ enum ComboResult {
 /// Excel-style dropdown: a filter field (type to narrow the list) plus arrow/Enter selection.
 /// `items` are `(value, display)`; the value is what comes back. When `forced` (keytip invoke)
 /// or clicked, the popup opens, focuses the filter field, and selects its text.
-fn editable_combo(
+pub(crate) fn editable_combo(
     ui: &mut Ui,
     anchor: &egui::Response,
     salt: &'static str,
@@ -483,6 +492,8 @@ fn menu_items(app: &mut SheetApp, ui: &mut Ui, items: &[(&str, &str, serde_json:
         if response.clicked() {
             if let Some(d) = id.strip_prefix("dialog:") {
                 app.open_dialog(d, p.clone());
+            } else if *id == "edit.paste" {
+                app.paste_from_clipboard();
             } else {
                 act(app, id, p.clone());
             }
@@ -495,17 +506,14 @@ fn home(app: &mut SheetApp, ui: &mut Ui) {
     let st = active_style(app);
     // Clipboard
     let paste = big_button(ui, Icon::Paste, "Paste", "Paste (⌘V)", true);
+    paste.widget_info(|| egui::WidgetInfo::labeled(egui::WidgetType::Button, ui.is_enabled(), "Paste"));
     for sequence in
         keytip_table::group_extension(app.keytips.prefix().unwrap_or_default(), &["edit.paste", "edit.pasteSpecial", "dialog:pasteSpecial"])
     {
         keytip(app, ui, sequence, paste.rect.center_bottom());
     }
     if paste.clicked() {
-        if let Some(text) = app.grid.system_clipboard.take() {
-            app.paste_external(text);
-        } else {
-            act(app, "edit.paste", json!({}));
-        }
+        app.paste_from_clipboard();
     }
     let paste_keys = matches!(app.keytips.prefix(), Some("HV" | "E"));
     // Keep a keyboard-opened menu anchored to the button when a pointer click
@@ -1426,7 +1434,13 @@ fn insert(app: &mut SheetApp, ui: &mut Ui) {
     let __k = big_button(ui, Icon::Chart, "Recommended\nCharts", "Recommended Charts", false);
     control_keytip(app, ui, &__k, "insert.recommendedCharts");
     if __k.clicked() {
-        act(app, "insert.recommendedCharts", json!({}));
+        match app.run("insert.recommendedCharts", json!({})) {
+            // The new chart is selected, as after inserting any other object (see insert.chart
+            // in dialogs.rs) — otherwise the prior cell/range selection is left in place, and
+            // Del right after inserting deletes the source data instead of the chart.
+            Ok(r) => app.selected_chart = r.get("chart").and_then(serde_json::Value::as_u64).and_then(|id| u32::try_from(id).ok()),
+            Err(e) => app.message = Some(("GridCraft".into(), crate::clean_error(&e))),
+        }
     }
     ui.vertical(|ui| {
         ui.horizontal(|ui| {
@@ -1698,13 +1712,13 @@ fn page_layout(app: &mut SheetApp, ui: &mut Ui) {
         let resp = ui.checkbox(&mut v, screen);
         control_keytip(app, ui, &resp, "view.gridlines");
         if resp.changed() || invoke(app, "view.gridlines") {
-            act(app, "view.gridlines", json!({"on": !v}));
+            act(app, "view.gridlines", json!({"on": checkbox_on(resp.changed(), v)}));
         }
         let mut p = sh.2;
         let resp = ui.checkbox(&mut p, print);
         control_keytip(app, ui, &resp, "pageLayout.printGridlines");
         if resp.changed() || invoke(app, "pageLayout.printGridlines") {
-            act(app, "pageLayout.printGridlines", json!({"on": !p}));
+            act(app, "pageLayout.printGridlines", json!({"on": checkbox_on(resp.changed(), p)}));
         }
     });
     ui.vertical(|ui| {
@@ -1713,13 +1727,13 @@ fn page_layout(app: &mut SheetApp, ui: &mut Ui) {
         let resp = ui.checkbox(&mut v, screen);
         control_keytip(app, ui, &resp, "view.headings");
         if resp.changed() || invoke(app, "view.headings") {
-            act(app, "view.headings", json!({"on": !v}));
+            act(app, "view.headings", json!({"on": checkbox_on(resp.changed(), v)}));
         }
         let mut p = sh.3;
         let resp = ui.checkbox(&mut p, print);
         control_keytip(app, ui, &resp, "pageLayout.printHeadings");
         if resp.changed() || invoke(app, "pageLayout.printHeadings") {
-            act(app, "pageLayout.printHeadings", json!({"on": !p}));
+            act(app, "pageLayout.printHeadings", json!({"on": checkbox_on(resp.changed(), p)}));
         }
     });
     let rtl = app.session.active().and_then(|d| d.wb.active()).is_some_and(|s| s.right_to_left);
@@ -2022,9 +2036,6 @@ fn review(app: &mut SheetApp, ui: &mut Ui) {
     if __k.clicked() {
         app.open_dialog("comment", json!({"threaded": true}));
     }
-    if big_button(ui, Icon::Comment, "Show\nComments", "Comments pane", false).clicked() {
-        app.grid.pane = Some("comments".into());
-    }
     let __k = big_button(ui, Icon::Delete, "Delete", "Delete Comment", false);
     control_keytip(app, ui, &__k, "review.deleteComment");
     if __k.clicked() {
@@ -2118,7 +2129,7 @@ fn view(app: &mut SheetApp, ui: &mut Ui) {
         let resp = ui.checkbox(&mut fb, lang.tr("Formula Bar"));
         control_keytip(app, ui, &resp, "view.formulaBar");
         if resp.changed() || invoke(app, "view.formulaBar") {
-            act(app, "view.formulaBar", json!({"on": !fb}));
+            act(app, "view.formulaBar", json!({"on": checkbox_on(resp.changed(), fb)}));
         }
         let mut g = s.0;
         let resp = ui.checkbox(&mut g, lang.tr("Gridlines"));
@@ -2447,11 +2458,13 @@ pub fn shortcut(app: &mut SheetApp, key: Key, m: Modifiers) {
         }
         Key::Semicolon => {
             // Insert today's date.
-            let today = gridcraft_engine::calc::now_serial().floor();
             let text = app
                 .session
                 .active()
-                .map(|d| gridcraft_engine::display::format(&gridcraft_engine::core::Value::Number(today), "m/d/yyyy", &d.wb).text)
+                .map(|d| {
+                    let today = gridcraft_engine::core::date::serial_in_system(d.wb.date_system, gridcraft_engine::calc::now_serial()).floor();
+                    gridcraft_engine::display::format(&gridcraft_engine::core::Value::Number(today), "m/d/yyyy", &d.wb).text
+                })
                 .unwrap_or_default();
             app.begin_edit(Some(text), false);
             None
@@ -2482,3 +2495,18 @@ mod title_bar_tests {
         assert_eq!(MAC_CONTENT_LEFT - lights_end, margin);
     }
 }
+
+#[cfg(test)]
+mod checkbox_on_tests {
+    use super::*;
+
+    #[test]
+    fn click_sends_the_new_checkbox_value_and_key_tip_the_opposite() {
+        // Click: the checkbox bool already holds the new choice.
+        assert!(!checkbox_on(true, false));
+        assert!(checkbox_on(true, true));
+        // Key tip: the bool still holds the current setting, so toggle it.
+        assert!(checkbox_on(false, false));
+        assert!(!checkbox_on(false, true));
+    }
+}
diff --git a/crates/ui-egui/src/tabs.rs b/crates/ui-egui/src/tabs.rs
index e55f575..f9669d6 100644
--- a/crates/ui-egui/src/tabs.rs
+++ b/crates/ui-egui/src/tabs.rs
@@ -1,7 +1,9 @@
 //! Sheet tabs and the status bar.
 
+use std::sync::Arc;
+
 use egui::{Align2, Color32, Rect, Sense, Stroke, StrokeKind, Ui, pos2, vec2};
-use gridcraft_engine::model::Visibility;
+use gridcraft_engine::model::{Sheet, Visibility};
 use serde_json::json;
 
 use crate::SheetApp;
@@ -14,6 +16,25 @@ fn rename_needs_focus(has_focus: bool, lost_focus: bool) -> bool {
     !has_focus && !lost_focus
 }
 
+/// Rows of the All Sheets navigator as `(workbook index, name)`. Hidden sheets stay out, like on the tab strip:
+/// Unhide is the way to reach them.
+fn navigator_items(sheets: &[Arc<Sheet>]) -> Vec<(String, String)> {
+    sheets.iter().enumerate().filter(|(_, s)| s.visibility == Visibility::Visible).map(|(i, s)| (i.to_string(), s.name.clone())).collect()
+}
+
+/// Switch to sheet `i` from the tab strip or the navigator. In point mode the formula being typed keeps going on the
+/// other sheet; otherwise the edit is committed first.
+fn activate_sheet(app: &mut SheetApp, i: usize) {
+    if app.editor.as_ref().is_some_and(|e| e.can_point()) {
+        let _ = app.session.run("sheet.activate", json!({"sheet": i}));
+    } else {
+        if app.editor.is_some() {
+            app.commit_edit(0, 0, false, false);
+        }
+        app.run_or_alert("sheet.activate", json!({"sheet": i}));
+    }
+}
+
 pub fn sheet_tabs(app: &mut SheetApp, ui: &mut Ui) {
     let t = Tokens::get(ui.ctx());
     egui::Panel::bottom("sheet_tabs").exact_size(32.0).frame(egui::Frame::NONE.fill(t.tab_bar)).show(ui, |ui| {
@@ -28,6 +49,16 @@ pub fn sheet_tabs(app: &mut SheetApp, ui: &mut Ui) {
             if crate::widgets::icon_button(ui, Icon::Right, t.text_dim, "Next sheet", vec2(24.0, 24.0)).clicked() {
                 app.run_or_alert("sheet.next", json!({}));
             }
+            let all = crate::widgets::icon_button(ui, Icon::SheetList, t.text_dim, "All sheets", vec2(24.0, 24.0));
+            all.widget_info(|| egui::WidgetInfo::labeled(egui::WidgetType::Button, true, "All sheets"));
+            let items = app.session.active().map(|d| navigator_items(&d.wb.sheets)).unwrap_or_default();
+            let active = app.session.active().map(|d| d.wb.active_sheet.to_string()).unwrap_or_default();
+            let rows: Vec<(&str, String)> = items.iter().map(|(i, name)| (i.as_str(), name.clone())).collect();
+            if let crate::ribbon::ComboResult::Picked(i) = crate::ribbon::editable_combo(ui, &all, "sheet_navigator", &active, &rows, false)
+                && let Ok(i) = i.parse::<usize>()
+            {
+                activate_sheet(app, i);
+            }
             ui.add_space(8.0);
             let Some(d) = app.session.active() else { return };
             let sheets: Vec<(usize, String, Option<[u8; 3]>, bool)> =
@@ -40,6 +71,15 @@ pub fn sheet_tabs(app: &mut SheetApp, ui: &mut Ui) {
             // Keep worksheet tabs in their own horizontally scrollable
             // viewport, leaving room for the New Sheet button and grid scrollbar.
             let tabs_width = (ui.available_width() - 180.0).max(100.0);
+            // Reveal the selected sheet after navigation or layout changes, but
+            // allow browsing other tabs without snapping back on every frame.
+            let reveal_key = egui::Id::new((d.uid, d.wb.active_sheet, &sheets, tabs_width.to_bits()));
+            let reveal_id = ui.id().with("worksheet_tabs_reveal");
+            let reveal_active = ui.ctx().data_mut(|data| {
+                let changed = data.get_temp::<egui::Id>(reveal_id) != Some(reveal_key);
+                data.insert_temp(reveal_id, reveal_key);
+                changed
+            });
             ui.allocate_ui_with_layout(vec2(tabs_width, 30.0), egui::Layout::left_to_right(egui::Align::Center), |ui| {
                 // Translate vertical wheel movement into horizontal
                 // worksheet-tab scrolling.
@@ -68,6 +108,9 @@ pub fn sheet_tabs(app: &mut SheetApp, ui: &mut Ui) {
                                 let tw = ui.painter().layout_no_wrap(name.clone(), font.clone(), t.text).size().x;
                                 let w = (tw + 32.0).max(72.0);
                                 let (r, resp) = ui.allocate_exact_size(vec2(w, 30.0), Sense::click_and_drag());
+                                if active && reveal_active {
+                                    resp.scroll_to_me(None);
+                                }
                                 let r = r.shrink2(vec2(0.0, 1.0));
                                 if active {
                                     ui.painter().rect_filled(Rect::from_min_max(pos2(r.left(), r.top() - 2.0), r.max), 4.0, t.tab_active);
@@ -106,15 +149,7 @@ pub fn sheet_tabs(app: &mut SheetApp, ui: &mut Ui) {
                                     ui.painter().text(r.center(), Align2::CENTER_CENTER, &name, font, if active { t.accent } else { t.text });
                                 }
                                 if resp.clicked() {
-                                    if app.editor.as_ref().is_some_and(|e| e.can_point()) {
-                                        // Point mode across sheets: switch without committing.
-                                        let _ = app.session.run("sheet.activate", json!({"sheet": i}));
-                                    } else {
-                                        if app.editor.is_some() {
-                                            app.commit_edit(0, 0, false, false);
-                                        }
-                                        app.run_or_alert("sheet.activate", json!({"sheet": i}));
-                                    }
+                                    activate_sheet(app, i);
                                 }
                                 if resp.double_clicked() {
                                     app.grid.renaming_tab = Some(i);
@@ -332,7 +367,9 @@ pub fn status_bar(app: &mut SheetApp, ui: &mut Ui) {
 
 #[cfg(test)]
 mod tests {
-    use super::rename_needs_focus;
+    use super::{navigator_items, rename_needs_focus};
+    use gridcraft_engine::model::{Sheet, Visibility};
+    use std::sync::Arc;
 
     #[test]
     fn rename_field_takes_focus_once_and_lets_go_on_commit() {
@@ -340,4 +377,14 @@ mod tests {
         assert!(!rename_needs_focus(true, false), "already focused: do not ask again");
         assert!(!rename_needs_focus(false, true), "Enter or click-away: must not take focus back");
     }
+
+    #[test]
+    fn navigator_lists_visible_sheets_by_workbook_index() {
+        let mut hidden = Sheet::new("Hidden");
+        hidden.visibility = Visibility::Hidden;
+        let mut very_hidden = Sheet::new("VeryHidden");
+        very_hidden.visibility = Visibility::VeryHidden;
+        let sheets = [Sheet::new("Data"), hidden, very_hidden, Sheet::new("Summary")].map(Arc::new);
+        assert_eq!(navigator_items(&sheets), vec![("0".to_string(), "Data".to_string()), ("3".to_string(), "Summary".to_string())]);
+    }
 }
diff --git a/crates/ui-egui/tests/clipboard.rs b/crates/ui-egui/tests/clipboard.rs
index 71fe336..bf835d8 100644
--- a/crates/ui-egui/tests/clipboard.rs
+++ b/crates/ui-egui/tests/clipboard.rs
@@ -3,9 +3,12 @@
 use std::cell::RefCell;
 use std::rc::Rc;
 
-use egui::{Event, OutputCommand};
+use egui::accesskit::Role;
+use egui::{Event, Modifiers, OutputCommand, PointerButton};
+use egui_kittest::kittest::Queryable as _;
 use gridcraft_engine::Session;
-use gridcraft_ui_egui::{Services, SheetApp};
+use gridcraft_engine::core::{CellRef, Value};
+use gridcraft_ui_egui::{Services, SheetApp, grid};
 use serde_json::json;
 
 fn harness(services: Services) -> egui_kittest::Harness<'static, SheetApp> {
@@ -116,3 +119,363 @@ fn copying_multiple_areas_copies_lined_up_areas_and_explains_the_rest() {
     assert_eq!(h.state().message.as_ref().map(|(_, text)| text.as_str()), Some("This action won't work on multiple selections."));
     assert_eq!(h.state().session.clipboard.as_ref().map(|c| c.areas.len()), Some(2), "the earlier copy stays");
 }
+
+#[test]
+fn enter_pastes_the_copied_cells_and_ends_copy_mode() {
+    // #845: with the marching ants showing, Enter pastes into the selection and cancels the copy.
+    let mut h = harness(Services::default());
+    h.input_mut().events.push(Event::Copy);
+    h.step();
+    h.state_mut().run("selection.set", json!({"cell": "D5"})).unwrap();
+    h.key_press(egui::Key::Enter);
+    h.run_steps(2);
+    let value = |r, c| h.state().session.active().and_then(|d| d.wb.active().map(|s| s.value(gridcraft_engine::core::CellRef::new(r, c))));
+    assert_eq!(value(4, 3), Some(gridcraft_engine::core::Value::text("Name")));
+    assert_eq!(value(5, 4), Some(gridcraft_engine::core::Value::number(42.0)));
+    assert!(h.state().session.clipboard.is_none(), "the marching ants are gone");
+    assert_eq!(h.state().session.active().map(|d| d.selection.active.a1()), Some("D5".to_string()), "Enter does not also move down");
+
+    // Copy mode is over: the next Enter just moves.
+    h.key_press(egui::Key::Enter);
+    h.run_steps(2);
+    assert_eq!(h.state().session.active().map(|d| d.selection.active.a1()), Some("D6".to_string()));
+fn clicking_the_ribbon_paste_button_or_its_menu_does_not_freeze() {
+    // #273: a click on Paste deadlocked the UI thread (a click-state query inside the egui context
+    // lock), so the frame never returned. Run the clicks on a worker and fail on a timeout instead of
+    // hanging the test run if that comes back.
+    let (done, finished) = std::sync::mpsc::channel();
+    let worker = std::thread::spawn(move || {
+        let cell = value_at;
+        let mut h = harness(Services::default());
+        h.state_mut().run("edit.copy", json!({"range": "A1:B2"})).unwrap();
+        h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+        // No host clipboard here (as on the web): GridCraft's own copy is pasted.
+        h.get_by_role_and_label(Role::Button, "Paste").click();
+        h.run_steps(3);
+        assert_eq!(cell(&h, "D4"), Some(Value::from("Name")));
+        assert_eq!(cell(&h, "E5"), Some(Value::number(42.0)));
+
+        // The secondary click opens the paste options menu; its items paste too.
+        h.state_mut().run("selection.set", json!({"cell": "G1"})).unwrap();
+        h.get_by_role_and_label(Role::Button, "Paste").click_secondary();
+        h.run_steps(3);
+        h.get_by_label("Paste Values").click();
+        h.run_steps(3);
+        assert_eq!(cell(&h, "G1"), Some(Value::from("Name")));
+        assert_eq!(cell(&h, "H2"), Some(Value::number(42.0)));
+        let _ = done.send(());
+    });
+    match finished.recv_timeout(std::time::Duration::from_secs(60)) {
+        Ok(()) => assert!(worker.join().is_ok()),
+        Err(std::sync::mpsc::RecvTimeoutError::Disconnected) => {
+            if let Err(panic) = worker.join() {
+                std::panic::resume_unwind(panic);
+            }
+        }
+        Err(std::sync::mpsc::RecvTimeoutError::Timeout) => panic!("clicking Paste froze the UI thread"),
+    }
+}
+
+type Harness = egui_kittest::Harness<'static, SheetApp>;
+
+fn value_at(h: &Harness, a1: &str) -> Option<Value> {
+    let at = gridcraft_engine::core::CellRef::parse(a1).unwrap();
+    h.state().session.active().and_then(|d| d.wb.active().map(|s| s.value(at)))
+}
+
+/// A host clipboard holding `text`, and how many times the app read it.
+fn system_clipboard(text: &str) -> (Rc<RefCell<(String, usize)>>, Services) {
+    let clipboard = Rc::new(RefCell::new((text.to_string(), 0)));
+    let read = clipboard.clone();
+    let services = Services {
+        paste_text: Some(Box::new(move || {
+            let mut clipboard = read.borrow_mut();
+            clipboard.1 += 1;
+            Some(clipboard.0.clone())
+        })),
+        ..Default::default()
+    };
+    (clipboard, services)
+}
+
+#[test]
+fn ribbon_paste_pastes_the_system_clipboard_like_cmd_v() {
+    // Text copied in another app: the Paste button pastes it, as Cmd/Ctrl+V does.
+    let (clipboard, services) = system_clipboard("x\t1\r\ny\t2\r\n");
+    let mut h = harness(services);
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    h.get_by_role_and_label(Role::Button, "Paste").click();
+    h.run_steps(2);
+    assert_eq!(clipboard.borrow().1, 1, "one clipboard read per click");
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("x")));
+    assert_eq!(value_at(&h, "E4"), Some(Value::number(1.0)));
+    assert_eq!(value_at(&h, "D5"), Some(Value::from("y")));
+    assert_eq!(value_at(&h, "E5"), Some(Value::number(2.0)));
+    assert!(h.state().message.is_none(), "{:?}", h.state().message);
+
+    // The clipboard text is GridCraft's own copy: the copy is pasted with its formulas.
+    h.state_mut().run("cell.set", json!({"cell": "A3", "input": "=B2*2"})).unwrap();
+    let copied = h.state_mut().run("edit.copy", json!({"range": "A3"})).unwrap();
+    clipboard.borrow_mut().0 = copied["text"].as_str().unwrap().to_string();
+    h.state_mut().run("selection.set", json!({"cell": "B9"})).unwrap();
+    h.get_by_role_and_label(Role::Button, "Paste").click();
+    h.run_steps(2);
+    let sh = h.state().session.active().unwrap().wb.active().unwrap();
+    assert_eq!(sh.cell(CellRef::parse("B9").unwrap()).unwrap().formula.as_ref().unwrap().text, "C8*2");
+
+    // Nothing on the system clipboard (an image, say): GridCraft's own copy is pasted.
+    clipboard.borrow_mut().0.clear();
+    h.state_mut().run("selection.set", json!({"cell": "B12"})).unwrap();
+    h.get_by_role_and_label(Role::Button, "Paste").click();
+    h.run_steps(2);
+    let sh = h.state().session.active().unwrap().wb.active().unwrap();
+    assert_eq!(sh.cell(CellRef::parse("B12").unwrap()).unwrap().formula.as_ref().unwrap().text, "C11*2");
+}
+
+#[test]
+fn paste_menu_items_paste_the_system_clipboard() {
+    let (clipboard, services) = system_clipboard("from menu");
+    let mut h = harness(services);
+    let ribbon = h.get_by_role_and_label(Role::Button, "Paste").rect();
+    let click_menu_paste = |h: &Harness| h.get_all_by_role_and_label(Role::Button, "Paste").find(|n| n.rect() != ribbon).unwrap().click();
+
+    // Home › Paste options menu › Paste.
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    h.get_by_role_and_label(Role::Button, "Paste").click_secondary();
+    h.run_steps(2);
+    click_menu_paste(&h);
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("from menu")));
+
+    // The cell's context menu › Paste.
+    clipboard.borrow_mut().0 = "from cell menu".into();
+    h.state_mut().run("selection.set", json!({"cell": "F6"})).unwrap();
+    let app = h.state();
+    let sh = app.session.active().unwrap().wb.active().unwrap();
+    let geo = grid::Geo::new(sh, app.grid.rect.unwrap(), app.view().scroll);
+    let pos = geo.cell_rect(sh, CellRef::parse("F6").unwrap()).center();
+    h.input_mut().events.push(Event::PointerMoved(pos));
+    for pressed in [true, false] {
+        h.input_mut().events.push(Event::PointerButton { pos, button: PointerButton::Secondary, pressed, modifiers: Modifiers::NONE });
+        h.run_steps(2);
+    }
+    assert!(h.state().grid.context_menu.is_some());
+    click_menu_paste(&h);
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "F6"), Some(Value::from("from cell menu")));
+    assert_eq!(clipboard.borrow().1, 2);
+}
+
+fn press(h: &mut Harness, key: egui::Key) {
+    for pressed in [true, false] {
+        h.input_mut().events.push(Event::Key { key, physical_key: None, pressed, repeat: false, modifiers: Modifiers::NONE });
+        if pressed && key != egui::Key::F10 {
+            h.input_mut().events.push(Event::Text(key.name().to_ascii_lowercase()));
+        }
+    }
+    h.run_steps(2);
+}
+
+#[test]
+fn keytip_copy_and_cut_reach_the_system_clipboard_and_ribbon_paste_pastes_them() {
+    // Home › Copy / Cut by keytip (Alt or F10, H, C / X) is the ribbon button: the host clipboard
+    // gets the copy, and Paste pastes it rather than older text from another app.
+    for (letter, cut) in [(egui::Key::C, false), (egui::Key::X, true)] {
+        let (clipboard, mut services) = system_clipboard("stale text from earlier");
+        let host = clipboard.clone();
+        services.copy_html = Some(Box::new(move |_, text| {
+            host.borrow_mut().0 = text.to_string();
+            Ok(())
+        }));
+        let mut h = harness(services);
+        for key in [egui::Key::F10, egui::Key::H, letter] {
+            press(&mut h, key);
+        }
+        assert_eq!(h.state().session.clipboard.as_ref().map(|c| c.cut), Some(cut), "{letter:?}");
+        assert_eq!(clipboard.borrow().0, "Name\tScore\nAda\t42\n", "{letter:?} publishes to the system clipboard");
+
+        h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+        h.get_by_role_and_label(Role::Button, "Paste").click();
+        h.run_steps(2);
+        assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")), "{letter:?}");
+        assert_eq!(value_at(&h, "E5"), Some(Value::number(42.0)), "{letter:?}");
+    }
+}
+
+#[test]
+fn ribbon_paste_prefers_a_programmatic_copy_until_other_text_is_copied() {
+    // A control-channel or MCP copy leaves the system clipboard alone. Its older text must not
+    // win over the copy; text copied in another app afterwards must.
+    let (clipboard, services) = system_clipboard("stale text from earlier");
+    let mut h = harness(services);
+    h.state_mut().run("edit.copy", json!({"range": "A1:B2"})).unwrap();
+    assert_eq!(clipboard.borrow().0, "stale text from earlier", "the system clipboard is untouched");
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    h.get_by_role_and_label(Role::Button, "Paste").click();
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")));
+    assert_eq!(value_at(&h, "E5"), Some(Value::number(42.0)));
+
+    clipboard.borrow_mut().0 = "copied elsewhere\t7".into();
+    h.state_mut().run("selection.set", json!({"cell": "G1"})).unwrap();
+    h.get_by_role_and_label(Role::Button, "Paste").click();
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "G1"), Some(Value::from("copied elsewhere")));
+    assert_eq!(value_at(&h, "H1"), Some(Value::number(7.0)));
+}
+
+fn has_formula(h: &Harness, a1: &str) -> bool {
+    let at = CellRef::parse(a1).unwrap();
+    h.state().session.active().and_then(|d| d.wb.active().and_then(|s| s.cell(at)).map(|c| c.formula.is_some())).unwrap_or(false)
+}
+
+/// Close the "Nothing to paste." alert so the ribbon takes clicks again.
+fn dismiss(h: &mut Harness) {
+    h.state_mut().message = None;
+    h.state_mut().toast = None;
+    h.run_steps(2);
+}
+
+fn click_paste(h: &mut Harness) {
+    h.get_by_role_and_label(Role::Button, "Paste").click();
+    h.run_steps(2);
+}
+
+#[test]
+fn a_pasted_ribbon_cut_is_not_pasted_again_from_the_system_clipboard() {
+    // Excel pastes a cut once. After the move, the cut's text is still on the system clipboard:
+    // a second Paste must not write it over the moved block (formulas would become values).
+    let (clipboard, mut services) = system_clipboard("stale text from earlier");
+    let host = clipboard.clone();
+    services.copy_html = Some(Box::new(move |_, text| {
+        host.borrow_mut().0 = text.to_string();
+        Ok(())
+    }));
+    let mut h = harness(services);
+    h.state_mut().run("cell.set", json!({"cell": "B3", "input": "=B2*2"})).unwrap();
+    h.state_mut().run("selection.set", json!({"range": "A1:B3"})).unwrap();
+    h.run_steps(2);
+    for key in [egui::Key::F10, egui::Key::H, egui::Key::X] {
+        press(&mut h, key);
+    }
+    assert_eq!(clipboard.borrow().0, "Name\tScore\nAda\t42\n\t84\n", "the cut is published");
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    click_paste(&mut h);
+    assert_eq!(value_at(&h, "E6"), Some(Value::number(84.0)));
+    assert!(has_formula(&h, "E6"), "the cut moves the formula");
+
+    click_paste(&mut h);
+    assert!(has_formula(&h, "E6"), "a second Paste leaves the moved formula alone");
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")));
+    assert!(h.state().toast.is_some() || h.state().message.is_some(), "Paste reports there is nothing to paste");
+
+    // Text copied in another app afterwards still pastes.
+    dismiss(&mut h);
+    clipboard.borrow_mut().0 = "copied elsewhere\t7".into();
+    h.state_mut().run("selection.set", json!({"cell": "H1"})).unwrap();
+    click_paste(&mut h);
+    assert_eq!(value_at(&h, "H1"), Some(Value::from("copied elsewhere")));
+    assert_eq!(value_at(&h, "I1"), Some(Value::number(7.0)));
+}
+
+#[test]
+fn a_pasted_programmatic_cut_does_not_paste_the_older_system_clipboard_text() {
+    // A control-channel or MCP cut leaves the system clipboard alone; once the cut has been
+    // pasted, the text that was there before it must not land on the moved data.
+    let (clipboard, services) = system_clipboard("stale");
+    let mut h = harness(services);
+    h.state_mut().run("edit.cut", json!({"range": "A1:B2"})).unwrap();
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    click_paste(&mut h);
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")));
+
+    click_paste(&mut h);
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")), "the moved data stays");
+    assert_eq!(value_at(&h, "E5"), Some(Value::number(42.0)));
+
+    dismiss(&mut h);
+    clipboard.borrow_mut().0 = "copied elsewhere".into();
+    click_paste(&mut h);
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("copied elsewhere")), "newer external text pastes");
+}
+
+#[test]
+fn the_paste_keytip_pastes_the_system_clipboard_like_the_paste_button() {
+    // Alt/F10, H, V, P is Home › Paste: it pastes text copied in another app.
+    let (_clipboard, services) = system_clipboard("external\t7");
+    let mut h = harness(services);
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    for key in [egui::Key::F10, egui::Key::H, egui::Key::V, egui::Key::P] {
+        press(&mut h, key);
+    }
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("external")));
+    assert_eq!(value_at(&h, "E4"), Some(Value::number(7.0)));
+    assert!(h.state().toast.is_none() && h.state().message.is_none());
+}
+
+#[test]
+fn cmd_v_after_a_pasted_cut_does_not_paste_the_cut_text_again() {
+    // Cmd/Ctrl+V hands the app the system clipboard's text, which still holds the cut after the
+    // move. Excel pastes a cut once: the second Cmd/Ctrl+V must leave the moved formulas alone.
+    let mut h = harness(Services::default());
+    h.state_mut().run("cell.set", json!({"cell": "B3", "input": "=B2*2"})).unwrap();
+    h.state_mut().run("selection.set", json!({"range": "A1:B3"})).unwrap();
+    h.input_mut().events.push(Event::Cut);
+    h.step();
+    let text = h
+        .output()
+        .platform_output
+        .commands
+        .iter()
+        .find_map(|c| match c {
+            OutputCommand::CopyText(text) => Some(text.clone()),
+            _ => None,
+        })
+        .expect("the cut is published");
+    h.run_steps(2);
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    h.input_mut().events.push(Event::Paste(text.clone()));
+    h.run_steps(2);
+    assert!(has_formula(&h, "E6"), "the cut moves the formula");
+
+    // The host may hand the text back with CRLF line endings.
+    h.input_mut().events.push(Event::Paste(text.replace('\n', "\r\n")));
+    h.run_steps(2);
+    assert!(has_formula(&h, "E6"), "a second Cmd/Ctrl+V leaves the moved formula alone");
+    assert_eq!(value_at(&h, "E6"), Some(Value::number(84.0)));
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")));
+    assert!(h.state().toast.is_some() || h.state().message.is_some(), "Paste reports there is nothing to paste");
+}
+
+#[test]
+fn the_cut_text_pastes_again_once_the_clipboard_has_held_other_text() {
+    // Once other text has been pasted, the clipboard has moved on from the cut: the same text
+    // copied again later (from another app, or a cell editor) is a new copy and pastes.
+    let mut h = harness(Services::default());
+    h.state_mut().run("selection.set", json!({"cell": "A1"})).unwrap();
+    h.input_mut().events.push(Event::Cut);
+    h.step();
+    let text = h
+        .output()
+        .platform_output
+        .commands
+        .iter()
+        .find_map(|c| match c {
+            OutputCommand::CopyText(text) => Some(text.clone()),
+            _ => None,
+        })
+        .expect("the cut is published");
+    h.run_steps(2);
+    h.state_mut().run("selection.set", json!({"cell": "D4"})).unwrap();
+    h.input_mut().events.push(Event::Paste(text.clone()));
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "D4"), Some(Value::from("Name")), "the cut moves A1");
+    h.state_mut().run("selection.set", json!({"cell": "G1"})).unwrap();
+    h.input_mut().events.push(Event::Paste("other".into()));
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "G1"), Some(Value::from("other")));
+    h.state_mut().run("selection.set", json!({"cell": "H1"})).unwrap();
+    h.input_mut().events.push(Event::Paste(text.replace('\n', "\r\n")));
+    h.run_steps(2);
+    assert_eq!(value_at(&h, "H1"), Some(Value::from("Name")), "the same text copied afresh pastes");
+}
diff --git a/crates/ui-egui/tests/comments_pane.rs b/crates/ui-egui/tests/comments_pane.rs
new file mode 100644
index 0000000..fe61508
--- /dev/null
+++ b/crates/ui-egui/tests/comments_pane.rs
@@ -0,0 +1,105 @@
+//! The Comments pane: one Show Comments button, and a pane that keeps its width (#710).
+
+use egui::{Event, Modifiers, PointerButton, Pos2, pos2, vec2};
+use egui_kittest::kittest::Queryable;
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::SheetApp;
+use serde_json::json;
+
+type Harness = egui_kittest::Harness<'static, SheetApp>;
+
+const WIDTH: f32 = 1200.0;
+
+fn harness() -> Harness {
+    let mut session = Session::new();
+    session.new_workbook();
+    let mut h = egui_kittest::Harness::builder().with_step_dt(1.0 / 60.0).with_size(vec2(WIDTH, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            app.logic(ui.ctx());
+            app.ui(ui);
+        },
+        SheetApp::new(session, Default::default()),
+    );
+    h.run_steps(4);
+    h
+}
+
+fn grid_right(h: &Harness) -> f32 {
+    h.state().grid.rect.unwrap().right()
+}
+
+/// A comment whose author line and reply row are wide enough to push the pane if they don't wrap.
+fn open_pane_on_long_comment(h: &mut Harness) {
+    let text = "A long comment that should wrap inside the pane instead of pushing it wider. ".repeat(6);
+    let author = "Someone With A Rather Long Display Name, Finance Department, Head Office";
+    h.state_mut().run("review.newComment", json!({"cell": "B2", "text": text, "author": author})).unwrap();
+    h.state_mut().run("review.showComments", json!({"on": true})).unwrap();
+    h.run_steps(3);
+}
+
+fn drag(h: &mut Harness, from: Pos2, to: Pos2) {
+    let press = |pos, pressed| Event::PointerButton { pos, button: PointerButton::Primary, pressed, modifiers: Modifiers::NONE };
+    h.input_mut().events.extend([Event::PointerMoved(from), press(from, true)]);
+    h.step();
+    for i in 1..=6 {
+        let t = i as f32 / 6.0;
+        h.input_mut().events.push(Event::PointerMoved(from + (to - from) * t));
+        h.step();
+    }
+    h.input_mut().events.push(press(to, false));
+    h.run_steps(3);
+}
+
+#[test]
+fn the_pane_does_not_grow_on_its_own_and_keeps_a_manual_resize() {
+    let mut h = harness();
+    // Between the grid and the right edge of the window, before any pane is open.
+    let gutter = WIDTH - grid_right(&h);
+    open_pane_on_long_comment(&mut h);
+    let opened = grid_right(&h);
+    assert!(WIDTH - opened < WIDTH / 2.0, "the pane opens at its default width, got {}", WIDTH - opened);
+    h.run_steps(60);
+    assert_eq!(grid_right(&h), opened, "the pane must not widen itself frame after frame");
+
+    // Drag the pane's left edge 150px to the left: the new width stays.
+    let edge = pos2(opened + gutter, 450.0);
+    drag(&mut h, edge, edge - vec2(150.0, 0.0));
+    let resized = grid_right(&h);
+    // The grab point is a few pixels off the exact edge, so allow some slack on the 150px.
+    assert!(opened - resized > 120.0, "the drag widens the pane, grid edge {opened} -> {resized}");
+    h.run_steps(60);
+    assert_eq!(grid_right(&h), resized, "a manual resize must hold");
+
+    // Dragged almost to the window's left edge, the pane stops at half the window.
+    let edge = pos2(resized + gutter, 450.0);
+    drag(&mut h, edge, pos2(60.0, 450.0));
+    assert!(grid_right(&h) > WIDTH / 2.0 - gutter - 30.0, "the pane is capped at half the window, grid edge {}", grid_right(&h));
+}
+
+/// How many separate ribbon buttons show `tip` when hovered, scanning the big-button row.
+fn buttons_with_tip(h: &mut Harness, tip: &str) -> usize {
+    h.ctx.all_styles_mut(|s| s.interaction.tooltip_delay = 0.0);
+    let (mut count, mut inside) = (0, false);
+    let mut x = 2.0;
+    while x < WIDTH {
+        h.input_mut().events.push(Event::PointerMoved(pos2(x, 120.0)));
+        h.run_steps(6);
+        let shown = h.query_all_by_value(tip).next().is_some();
+        if shown && !inside {
+            count += 1;
+        }
+        inside = shown;
+        x += 8.0;
+    }
+    count
+}
+
+#[test]
+fn review_has_a_single_show_comments_button() {
+    let mut h = harness();
+    h.state_mut().ui.ribbon_tab = "Review".into();
+    h.run_steps(2);
+    // The scan has to find a known single button, or a count of one below would prove nothing.
+    assert_eq!(buttons_with_tip(&mut h, "New Comment"), 1);
+    assert_eq!(buttons_with_tip(&mut h, "Comments pane"), 1);
+}
diff --git a/crates/ui-egui/tests/file_menu.rs b/crates/ui-egui/tests/file_menu.rs
index c6ef2b2..691eef3 100644
--- a/crates/ui-egui/tests/file_menu.rs
+++ b/crates/ui-egui/tests/file_menu.rs
@@ -171,3 +171,49 @@ fn save_as_offers_pdf_and_leaves_the_workbook_file_alone() {
     assert!(d.path.is_none() && d.is_dirty(), "a PDF is a copy, not the workbook's file");
     let _ = std::fs::remove_dir_all(&dir);
 }
+
+fn pdf_picker_harness(dir: &std::path::Path) -> (Arc<Mutex<Vec<String>>>, egui_kittest::Harness<'static, SheetApp>) {
+    let asked = Arc::new(Mutex::new(Vec::<String>::new()));
+    let (capture, target) = (asked.clone(), dir.to_path_buf());
+    let h = harness(Services {
+        pick_save: Some(Box::new(move |suggested| {
+            capture.lock().unwrap().push(suggested.to_string());
+            Some(target.join("Report.xlsx").to_string_lossy().into_owned())
+        })),
+        ..Default::default()
+    });
+    (asked, h)
+}
+
+#[test]
+fn the_palette_export_as_pdf_asks_where_to_save() {
+    let dir = std::env::temp_dir().join(format!("gridcraft-export-pdf-palette-{}", std::process::id()));
+    std::fs::create_dir_all(&dir).unwrap();
+    let (asked, mut h) = pdf_picker_harness(&dir);
+    h.state_mut().run("cell.set", serde_json::json!({"cell": "A1", "input": "42"})).unwrap();
+    // The palette and menus go through run_or_alert.
+    h.state_mut().run_or_alert("file.exportPdf", serde_json::json!({}));
+    assert!(asked.lock().unwrap().first().is_some_and(|s| s.ends_with(".pdf")), "the picker is offered a .pdf name");
+    assert!(std::fs::read(dir.join("Report.pdf")).unwrap().starts_with(b"%PDF-"), "the PDF is written, whatever extension the picker returned");
+    assert!(h.state().message.is_none());
+    let d = h.state().session.active().unwrap();
+    assert!(d.path.is_none(), "a PDF is a copy, not the workbook's file");
+    // Other params survive the round trip through the picker.
+    h.state_mut().run_or_alert("file.exportPdf", serde_json::json!({"range": "nope"}));
+    assert!(h.state().message.is_some(), "a bad range is reported, not swallowed");
+    // A path in the params skips the picker.
+    let before = asked.lock().unwrap().len();
+    let named = dir.join("Named.pdf");
+    h.state_mut().run_or_alert("file.exportPdf", serde_json::json!({"path": named.to_string_lossy()}));
+    assert_eq!(asked.lock().unwrap().len(), before);
+    assert!(named.exists());
+    let _ = std::fs::remove_dir_all(&dir);
+}
+
+#[test]
+fn a_cancelled_export_pdf_picker_writes_nothing() {
+    let mut h = harness(Services { pick_save: Some(Box::new(|_| None)), ..Default::default() });
+    h.state_mut().run_or_alert("file.exportPdf", serde_json::json!({}));
+    assert!(h.state().message.is_none());
+    assert!(h.state_mut().session.take_ui_requests().is_empty());
+}
diff --git a/crates/ui-egui/tests/fill_handle_double_click.rs b/crates/ui-egui/tests/fill_handle_double_click.rs
new file mode 100644
index 0000000..88b8737
--- /dev/null
+++ b/crates/ui-egui/tests/fill_handle_double_click.rs
@@ -0,0 +1,59 @@
+//! Double-clicking the fill handle fills down to the neighbouring column's last used row,
+//! even with the pointer up for a frame between the two clicks.
+
+use egui::{Event, Modifiers, PointerButton, Pos2, vec2};
+use gridcraft_engine::Session;
+use gridcraft_engine::core::{CellRef, Value};
+use gridcraft_ui_egui::{SheetApp, grid::Geo};
+use serde_json::json;
+
+fn harness() -> egui_kittest::Harness<'static, SheetApp> {
+    let mut session = Session::new();
+    session.new_workbook();
+    session.execute("range.setValues", json!({"range": "A1", "values": [[1], [2], [3], [4], [5], [6]]})).unwrap();
+    session.execute("range.setValues", json!({"range": "B1", "values": [[10], [20], [30]]})).unwrap();
+    session.execute("selection.set", json!({"range": "B1:B3"})).unwrap();
+    let mut h = egui_kittest::Harness::builder().with_step_dt(1.0 / 60.0).with_size(vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            app.logic(ui.ctx());
+            app.ui(ui);
+        },
+        SheetApp::new(session, Default::default()),
+    );
+    h.run_steps(4);
+    h
+}
+
+fn handle(h: &egui_kittest::Harness<'_, SheetApp>) -> Pos2 {
+    let app = h.state();
+    let sheet = app.session.active().unwrap().wb.active().unwrap();
+    let geo = Geo::new(sheet, app.grid.rect.unwrap(), app.view().scroll);
+    geo.cell_rect(sheet, CellRef::new(2, 1)).right_bottom() - vec2(1.0, 1.0)
+}
+
+fn button(h: &mut egui_kittest::Harness<'_, SheetApp>, pos: Pos2, pressed: bool) {
+    h.input_mut()
+        .events
+        .extend([Event::PointerMoved(pos), Event::PointerButton { pos, button: PointerButton::Primary, pressed, modifiers: Modifiers::NONE }]);
+    h.step();
+}
+
+fn number(h: &egui_kittest::Harness<'_, SheetApp>, row: u32) -> Value {
+    h.state().session.active().unwrap().wb.active().unwrap().value(CellRef::new(row, 1))
+}
+
+#[test]
+fn double_click_on_the_fill_handle_fills_down_with_a_frame_between_the_clicks() {
+    let mut h = harness();
+    let pos = handle(&h);
+    button(&mut h, pos, true);
+    button(&mut h, pos, false);
+    h.step(); // One idle frame between the clicks, well inside the double-click interval.
+    button(&mut h, pos, true);
+    button(&mut h, pos, false);
+    h.run_steps(2);
+
+    assert_eq!([number(&h, 3), number(&h, 4), number(&h, 5)], [Value::Number(40.0), Value::Number(50.0), Value::Number(60.0)]);
+    assert_eq!(h.state().session.active().unwrap().selection.a1(), "B1:B6");
+    assert_eq!(h.state().session.journal.iter().filter(|(id, _)| id == "edit.autoFill").count(), 1);
+}
diff --git a/crates/ui-egui/tests/filter_list_scroll.rs b/crates/ui-egui/tests/filter_list_scroll.rs
new file mode 100644
index 0000000..35406fa
--- /dev/null
+++ b/crates/ui-egui/tests/filter_list_scroll.rs
@@ -0,0 +1,61 @@
+//! The AutoFilter value list scrolls with the pointer anywhere over it, not only over the values
+//! themselves (issue #432): the list takes the menu's full width, so its scroll bar and wheel area do too.
+
+use egui::{Event, Modifiers, MouseWheelUnit, PointerButton, TouchPhase, pos2, vec2};
+use egui_kittest::kittest::Queryable;
+use gridcraft_engine::Session;
+use gridcraft_engine::core::CellRef;
+use gridcraft_ui_egui::{SheetApp, grid};
+use serde_json::json;
+
+type Harness = egui_kittest::Harness<'static, SheetApp>;
+
+/// A1:A81 holds a header and 80 distinct values, with the AutoFilter's menu open on column A.
+fn filter_menu_on_a_long_list() -> Harness {
+    let mut session = Session::new();
+    session.new_workbook();
+    let mut values = vec![vec![json!("Code")]];
+    values.extend((1..=80).map(|i| vec![json!(format!("ITEM-{i:03}"))]));
+    session.execute("range.setValues", json!({"range": "A1", "values": values})).unwrap();
+    session.execute("data.filter", json!({"range": "A1:A81"})).unwrap();
+    let mut h = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            app.logic(ui.ctx());
+            app.ui(ui);
+        },
+        SheetApp::new(session, Default::default()),
+    );
+    h.run_steps(4);
+    let button = {
+        let app = h.state();
+        let sh = app.session.active().unwrap().wb.active().unwrap();
+        let geo = grid::Geo::new(sh, app.grid.rect.unwrap(), app.view().scroll);
+        grid::filter_button_rect(&geo, sh, CellRef::parse("A1").unwrap()).center()
+    };
+    h.input_mut().events.push(Event::PointerMoved(button));
+    for pressed in [true, false] {
+        h.input_mut().events.push(Event::PointerButton { pos: button, button: PointerButton::Primary, pressed, modifiers: Modifiers::NONE });
+    }
+    h.run_steps(4);
+    assert!(h.state().grid.filter_menu.is_some(), "the filter menu opens");
+    h
+}
+
+#[test]
+fn filter_list_scrolls_with_the_pointer_right_of_the_values() {
+    let mut h = filter_menu_on_a_long_list();
+    let first = h.get_by_label("ITEM-001").rect();
+    // The menu is 230 points wide; the value labels end well before this point.
+    let pointer = pos2(first.left() + 200.0, first.center().y);
+    h.input_mut().events.push(Event::PointerMoved(pointer));
+    h.run_steps(2);
+    h.input_mut().events.push(Event::MouseWheel {
+        unit: MouseWheelUnit::Line,
+        delta: vec2(0.0, -3.0),
+        phase: TouchPhase::Move,
+        modifiers: Modifiers::NONE,
+    });
+    h.run_steps(20);
+    let now = h.query_by_label("ITEM-001").map(|n| n.rect().top());
+    assert!(now.is_none_or(|y| y < first.top() - 20.0), "the wheel scrolls the list: ITEM-001 was at {}, now {now:?}", first.top());
+}
diff --git a/crates/ui-egui/tests/formula_locale.rs b/crates/ui-egui/tests/formula_locale.rs
index fe21218..8558693 100644
--- a/crates/ui-egui/tests/formula_locale.rs
+++ b/crates/ui-egui/tests/formula_locale.rs
@@ -1,7 +1,7 @@
 //! Language selection must affect UI entry, never the canonical engine/file boundary.
 use gridcraft_engine::{
     Session,
-    core::{CellRef, Value},
+    core::{CellError, CellRef, Value},
 };
 use gridcraft_ui_egui::{SheetApp, UiState, i18n::Language};
 use serde_json::json;
@@ -201,3 +201,21 @@ fn czech_interface_retains_its_canonical_formula_fallback() {
     let restored: UiState = serde_json::from_str(&serde_json::to_string(&app.ui).unwrap()).unwrap();
     assert_eq!(restored.language, Language::Cs);
 }
+
+#[test]
+fn user_defined_prefix_is_hidden_while_editing_and_kept_on_commit() {
+    // Excel shows `_xludf.EOMONTH()` as `=EOMONTH()`; the cell still holds the user-defined call
+    // (#726), and committing the edit unchanged must not turn it into the built-in.
+    let mut app = app();
+    app.run("cell.set", json!({"cell":"A1","input":"=_xludf.EOMONTH()&_xludf.CONCAT(\"_xludf.x\")"})).unwrap();
+    app.begin_edit(None, true);
+    assert_eq!(app.editor.as_ref().unwrap().text, "=EOMONTH()&CONCAT(\"_xludf.x\")");
+    assert!(app.commit_edit(0, 0, false, false));
+    assert_eq!(formula(&app), "_xludf.EOMONTH()&_xludf.CONCAT(\"_xludf.x\")");
+    assert_eq!(app.session.active().unwrap().wb.active().unwrap().value(CellRef::new(0, 0)), Value::Error(CellError::Name));
+    app.run("app.language.set", json!({"language":"es"})).unwrap();
+    app.begin_edit(None, true);
+    assert_eq!(app.editor.as_ref().unwrap().text, "=EOMONTH()&CONCAT(\"_xludf.x\")");
+    assert!(app.commit_edit(0, 0, false, false));
+    assert_eq!(formula(&app), "_xludf.EOMONTH()&_xludf.CONCAT(\"_xludf.x\")");
+}
diff --git a/crates/ui-egui/tests/formula_point_headers.rs b/crates/ui-egui/tests/formula_point_headers.rs
new file mode 100644
index 0000000..4313fb9
--- /dev/null
+++ b/crates/ui-egui/tests/formula_point_headers.rs
@@ -0,0 +1,75 @@
+//! Point mode on the headers: while a formula waits for a reference, a header click inserts a
+//! whole-column or whole-row reference, driven through real egui pointer events.
+
+use egui::{Event, Modifiers, PointerButton, Pos2, pos2, vec2};
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::{SheetApp, grid::Geo};
+use serde_json::json;
+
+fn harness() -> egui_kittest::Harness<'static, SheetApp> {
+    let mut session = Session::new();
+    session.new_workbook();
+    session.execute("selection.set", json!({"range": "F8"})).unwrap();
+    let mut h = egui_kittest::Harness::builder().with_step_dt(1.0 / 60.0).with_size(vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            app.logic(ui.ctx());
+            app.ui(ui);
+        },
+        SheetApp::new(session, Default::default()),
+    );
+    h.run_steps(4);
+    h.state_mut().begin_edit(Some("=SUM(".into()), false);
+    h.run_steps(2);
+    h
+}
+
+fn header_center(h: &egui_kittest::Harness<'_, SheetApp>, rows: bool, index: u32) -> Pos2 {
+    let app = h.state();
+    let sheet = app.session.active().unwrap().wb.active().unwrap();
+    let geo = Geo::new(sheet, app.grid.rect.unwrap(), app.view().scroll);
+    if rows {
+        pos2(geo.rect.left() + geo.header_w * 0.5, geo.y(sheet, index) + sheet.row_height(index) * geo.z * 0.5)
+    } else {
+        pos2(geo.x(sheet, index) + sheet.col_width(index) * geo.z * 0.5, geo.rect.top() + geo.header_h * 0.5)
+    }
+}
+
+fn click(h: &mut egui_kittest::Harness<'_, SheetApp>, pos: Pos2) {
+    for pressed in [true, false] {
+        h.input_mut()
+            .events
+            .extend([Event::PointerMoved(pos), Event::PointerButton { pos, button: PointerButton::Primary, pressed, modifiers: Modifiers::NONE }]);
+        h.step();
+    }
+    h.run_steps(2);
+}
+
+#[test]
+fn column_header_click_inserts_a_column_reference() {
+    let mut h = harness();
+    let at = header_center(&h, false, 2);
+    click(&mut h, at);
+    let app = h.state();
+    assert_eq!(app.editor.as_ref().map(|e| e.text.as_str()), Some("=SUM(C:C"));
+    assert_eq!(app.session.active().unwrap().selection.current().a1(), "F8");
+}
+
+#[test]
+fn row_header_click_inserts_a_row_reference() {
+    let mut h = harness();
+    let at = header_center(&h, true, 3);
+    click(&mut h, at);
+    let app = h.state();
+    assert_eq!(app.editor.as_ref().map(|e| e.text.as_str()), Some("=SUM(4:4"));
+    assert_eq!(app.session.active().unwrap().selection.current().a1(), "F8");
+}
+
+#[test]
+fn a_second_header_click_replaces_the_pointed_reference() {
+    let mut h = harness();
+    let first = header_center(&h, false, 2);
+    click(&mut h, first);
+    let second = header_center(&h, false, 4);
+    click(&mut h, second);
+    assert_eq!(h.state().editor.as_ref().map(|e| e.text.as_str()), Some("=SUM(E:E"));
+}
diff --git a/crates/ui-egui/tests/interaction.rs b/crates/ui-egui/tests/interaction.rs
index 7093933..b7b66bd 100644
--- a/crates/ui-egui/tests/interaction.rs
+++ b/crates/ui-egui/tests/interaction.rs
@@ -191,6 +191,25 @@ fn arrows_escape_and_undo() {
     assert_eq!(value(&h, "B2"), Value::Empty);
 }
 
+#[test]
+fn shift_arrows_in_point_mode_extend_from_the_pointed_cell() {
+    let mut s = blank();
+    s.execute("selection.set", json!({"cell": "A11"})).unwrap();
+    let mut h = harness(s);
+    text(&mut h, "=SUM(");
+    key(&mut h, Key::ArrowUp, Modifiers::NONE);
+    let edited = |h: &egui_kittest::Harness<'static, SheetApp>| h.state().editor.as_ref().map(|e| e.text.clone());
+    assert_eq!(edited(&h).as_deref(), Some("=SUM(A10"));
+    // Shift is held down, as on a real keyboard: the backend reports it before the arrow keys.
+    h.input_mut().events.push(Event::ModifiersChanged(Modifiers::SHIFT));
+    for expected in ["=SUM(A9:A10", "=SUM(A8:A10", "=SUM(A7:A10"] {
+        key(&mut h, Key::ArrowUp, Modifiers::SHIFT);
+        assert_eq!(edited(&h).as_deref(), Some(expected));
+    }
+    key(&mut h, Key::ArrowDown, Modifiers::SHIFT);
+    assert_eq!(edited(&h).as_deref(), Some("=SUM(A8:A10"), "Shift+Down shrinks back towards the anchor");
+}
+
 #[test]
 fn shortcuts_format_and_extend() {
     let mut s = blank();
@@ -224,6 +243,25 @@ fn delete_key_removes_the_selected_chart() {
     assert_eq!(value(&h, "A1"), Value::Number(1.0));
 }
 
+#[test]
+fn inserted_chart_is_selected_so_delete_removes_it() {
+    // #668, #256: after Insert › Chart the selection stayed on the source cells, so Delete
+    // cleared the data and left the chart behind.
+    let mut session = blank();
+    session.execute("range.setValues", json!({"range": "A1:B2", "values": [[1, 2], [3, 4]]})).unwrap();
+    session.execute("selection.set", json!({"range": "A1:B2"})).unwrap();
+    let mut h = harness(session);
+
+    let id = h.state_mut().run("insert.chart", json!({"type": "column"})).unwrap()["chart"].as_u64().unwrap() as u32;
+    h.run_steps(2);
+    assert_eq!(h.state().selected_chart, Some(id), "the new chart is selected");
+
+    key(&mut h, Key::Delete, Modifiers::NONE);
+
+    assert!(h.state().session.active().unwrap().wb.active().unwrap().charts.is_empty());
+    assert_eq!(value(&h, "A1"), Value::Number(1.0));
+}
+
 #[test]
 fn renders_every_ribbon_tab_without_panicking() {
     let mut s = Session::new();
@@ -279,6 +317,25 @@ fn language_switch_translates_the_ribbon_and_persists() {
     assert_eq!(h.state().ui.language, Language::En);
 }
 
+#[test]
+fn format_cells_draws_its_labels_in_the_interface_language() {
+    let mut h = harness(blank());
+    h.state_mut().run("app.language.set", json!({"language": "de"})).unwrap();
+    h.state_mut().open_dialog("formatCells", json!({"tab": "Number"}));
+    h.run_steps(2);
+    assert!(h.query_by_label("Wissenschaftlich").is_some(), "the Number tab's categories are translated");
+    assert!(h.query_by_label("Scientific").is_none(), "no English category is left");
+    h.get_by_label("Wissenschaftlich").click();
+    h.run_steps(2);
+    let style = &h.state().dialog.as_ref().unwrap().values["style"];
+    assert_eq!(style["num_fmt"], json!("0.00E+00"), "a translated category still applies its code");
+    h.state_mut().dialog = None;
+    h.state_mut().run("app.language.set", json!({"language": "en"})).unwrap();
+    h.state_mut().open_dialog("formatCells", json!({"tab": "Number"}));
+    h.run_steps(2);
+    assert!(h.query_by_label("Scientific").is_some(), "English is unchanged");
+}
+
 #[test]
 fn name_manager_new_and_edit_open_the_name_dialog_and_come_back() {
     // #238: New… in the Name Manager did nothing (the manager put itself back over the dialog it
@@ -460,6 +517,33 @@ fn solver_dialog_loads_the_saved_model_and_results_can_restore() {
     assert_eq!(value(&h, "B1"), Value::Number(0.0));
 }
 
+#[test]
+fn solver_results_write_the_chosen_reports() {
+    let mut s = blank();
+    for (c, v) in [("A1", "0"), ("A2", "0"), ("B1", "=3*A1+5*A2"), ("B2", "=2*A2"), ("B3", "=3*A1+2*A2")] {
+        s.execute("cell.set", json!({"cell": c, "input": v})).unwrap();
+    }
+    let r = s
+        .execute(
+            "data.solver",
+            json!({"objective": "B1", "variables": "A1:A2", "constraints": ["A1 <= 4", "B2 <= 12", "B3 <= 18"], "method": "simplex"}),
+        )
+        .unwrap();
+    let mut h = harness(s);
+    // Restore Original Values with the Answer and Limits reports: the cells go back, the reports stay.
+    h.state_mut().open_dialog("solverResults", r);
+    for key in ["restore", "answerReport", "limitsReport"] {
+        h.state_mut().dialog.as_mut().unwrap().values.insert(key.into(), json!(true));
+    }
+    h.run_steps(2);
+    key(&mut h, Key::Enter, Modifiers::NONE);
+    assert!(h.state().dialog.is_none());
+    assert!(h.state().message.is_none(), "{:?}", h.state().message);
+    let names: Vec<String> = h.state().session.active().unwrap().wb.sheets.iter().map(|s| s.name.clone()).collect();
+    assert_eq!(names, ["Answer Report 1", "Limits Report 1", "Sheet1"]);
+    assert_eq!(value(&h, "B1"), Value::Number(0.0));
+}
+
 #[test]
 fn about_renders_every_tab() {
     let mut h = harness(blank());
diff --git a/crates/ui-egui/tests/keyboard_shortcuts.rs b/crates/ui-egui/tests/keyboard_shortcuts.rs
index 82d3f2f..ae0ce5c 100644
--- a/crates/ui-egui/tests/keyboard_shortcuts.rs
+++ b/crates/ui-egui/tests/keyboard_shortcuts.rs
@@ -149,3 +149,68 @@ fn space_shortcuts_per_platform() {
     // Cmd+Space is Spotlight on macOS.
     assert_eq!(space(mac_cmd, true), None);
 }
+
+#[test]
+fn alt_down_opens_autofilter_headers_without_changing_the_workbook() {
+    for rtl in [false, true] {
+        for cell in ["A1", "B1"] {
+            let mut session = book(cell);
+            session.execute("data.filter", json!({"range": "A1:B3"})).unwrap();
+            session.execute("view.rightToLeft", json!({"on": rtl})).unwrap();
+            let mut h = harness(session);
+            let before = h.state().session.active().unwrap().wb.clone();
+            key(&mut h, Key::ArrowDown, Modifiers::ALT);
+            let (column, at) = h.state().grid.filter_menu.expect("Alt+Down must open the filter header menu");
+            let d = h.state().session.active().unwrap();
+            let active = CellRef::parse(cell).unwrap();
+            assert_eq!(column, active.col);
+            assert_eq!(d.selection.active, active);
+            assert_eq!(d.wb, before);
+            let sh = d.wb.active().unwrap();
+            let geo = gridcraft_ui_egui::grid::Geo::new(sh, h.state().grid.rect.unwrap(), h.state().view().scroll);
+            assert_eq!(at, geo.mirror_pos(gridcraft_ui_egui::grid::filter_button_rect(&geo, sh, active).center()));
+            // Opening focuses the existing search box; typing must not edit the header.
+            h.input_mut().events.push(Event::Text("1".into()));
+            h.run_steps(2);
+            assert_eq!(h.ctx.data(|data| data.get_temp::<String>(egui::Id::new(("filter_search", column)))).as_deref(), Some("1"));
+            assert!(h.state().editor.is_none());
+            assert_eq!(h.state().session.active().unwrap().wb, before);
+            key(&mut h, Key::Escape, Modifiers::NONE);
+            assert!(h.state().grid.filter_menu.is_none());
+        }
+    }
+}
+
+#[test]
+fn alt_down_keeps_validation_priority_and_plain_down_navigation() {
+    let mut session = book("A1");
+    session.execute("data.filter", json!({"range": "A1:B3"})).unwrap();
+    session.execute("data.validation", json!({"range": "A1", "type": "list", "formula1": "\"First,Second\""})).unwrap();
+    let mut h = harness(session);
+    key(&mut h, Key::ArrowDown, Modifiers::ALT);
+    assert_eq!(h.state().grid.list_picker, Some(CellRef::parse("A1").unwrap()));
+    assert!(h.state().grid.filter_menu.is_none());
+    key(&mut h, Key::Escape, Modifiers::NONE);
+    key(&mut h, Key::ArrowDown, Modifiers::NONE);
+    assert_eq!(h.state().session.active().unwrap().selection.active.a1(), "A2");
+    assert!(h.state().grid.filter_menu.is_none());
+    key(&mut h, Key::ArrowDown, Modifiers::ALT);
+    assert!(h.state().grid.filter_menu.is_none(), "a data cell has no filter button");
+    assert_eq!(h.state().session.active().unwrap().selection.active.a1(), "A2");
+}
+
+#[test]
+fn alt_down_only_opens_enabled_table_filter_buttons() {
+    for enabled in [false, true] {
+        let mut session = book("B1");
+        session.execute("insert.table", json!({"range": "A1:B3"})).unwrap();
+        if !enabled {
+            session.execute("table.headerRow", json!({"on": false})).unwrap();
+        }
+        session.execute("selection.set", json!({"cell": "B1"})).unwrap();
+        let mut h = harness(session);
+        key(&mut h, Key::ArrowDown, Modifiers::ALT);
+        assert_eq!(h.state().grid.filter_menu.map(|(column, _)| column), enabled.then_some(1));
+        assert_eq!(h.state().session.active().unwrap().selection.active.a1(), "B1");
+    }
+}
diff --git a/crates/ui-egui/tests/keytips_generated.rs b/crates/ui-egui/tests/keytips_generated.rs
index 50c5731..6535548 100644
--- a/crates/ui-egui/tests/keytips_generated.rs
+++ b/crates/ui-egui/tests/keytips_generated.rs
@@ -1062,7 +1062,7 @@ fn keytip_hv_() {
 fn keytip_hvp_() {
     let mut h = harness(blank());
     sequence(&mut h, "HVP", false);
-    assert!(h.state().message.is_some() || h.state().toast.is_some(), "HVP must invoke edit.pasteSpecial and surface its missing-params error");
+    assert!(h.state().message.is_some() || h.state().toast.is_some(), "HVP must invoke edit.paste and surface its missing-params error");
 }
 
 #[test]
diff --git a/crates/ui-egui/tests/page_layout_view.rs b/crates/ui-egui/tests/page_layout_view.rs
index f8850b3..b2e80d0 100644
--- a/crates/ui-egui/tests/page_layout_view.rs
+++ b/crates/ui-egui/tests/page_layout_view.rs
@@ -12,8 +12,20 @@ use serde_json::json;
 type Harness = egui_kittest::Harness<'static, SheetApp>;
 
 fn fixture() -> Harness {
+    fixture_with(false, None)
+}
+
+/// `rtl` mirrors the sheet; `setup` is extra `pageLayout.pageSetup` params.
+fn fixture_with(rtl: bool, setup: Option<serde_json::Value>) -> Harness {
     let mut session = Session::new();
     session.new_workbook();
+    if rtl {
+        session.execute("view.rightToLeft", json!({"on": true})).unwrap();
+    }
+    if let Some(p) = setup {
+        session.execute("cell.set", json!({"cell": "Z1", "input": "wide"})).unwrap();
+        session.execute("pageLayout.pageSetup", p).unwrap();
+    }
     for r in 1..=60 {
         session.execute("cell.set", json!({"cell": format!("A{r}"), "input": r.to_string()})).unwrap();
     }
@@ -162,3 +174,201 @@ fn insert_header_and_footer_switches_to_page_layout_view() {
     let e = h.state().grid.hf_edit.as_ref().expect("the header is being edited");
     assert_eq!((e.footer, e.section, e.texts[0].as_str()), (false, 1, "Left"));
 }
+
+fn margins(h: &Harness) -> [f32; 6] {
+    h.state().session.doc().unwrap().wb.active().unwrap().print.margins
+}
+
+fn mouse(h: &mut Harness, ev: Event) {
+    h.input_mut().events.push(ev);
+    h.step();
+}
+
+#[test]
+fn dragging_a_ruler_edge_previews_commits_on_release_as_one_undo_step_and_esc_cancels() {
+    let mut h = fixture();
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let start_margins = margins(&h);
+    let ruler_y = h.state().grid.rect.unwrap().top() + 9.0;
+    let edge = pos2(screen(&g, pg.page_x(0) + pg.margins[0], 0.0).x, ruler_y);
+    // One inch further in = 96 layout pixels at 100% print scale; use the screen scale to be exact.
+    let per_inch = (72.0 / (pg.paper_pt.0 as f64 / pg.page_w)) as f32 * g.z;
+    let target = pos2(edge.x + per_inch, ruler_y);
+    h.run_steps(40);
+    mouse(&mut h, Event::PointerMoved(edge));
+    mouse(&mut h, Event::PointerButton { pos: edge, button: PointerButton::Primary, pressed: true, modifiers: Modifiers::NONE });
+    mouse(&mut h, Event::PointerMoved(pos2(edge.x + 5.0, ruler_y)));
+    mouse(&mut h, Event::PointerMoved(target));
+    h.run_steps(2);
+    // Live preview: the page content moved, the document did not change yet.
+    let live = geo(&h).paper.unwrap().margins[0];
+    assert!(live > pg.margins[0] + 1.0, "{live} vs {}", pg.margins[0]);
+    assert_eq!(margins(&h), start_margins);
+    let want = (start_margins[0] + 1.0 * 1.0).min(10.0);
+    mouse(&mut h, Event::PointerButton { pos: target, button: PointerButton::Primary, pressed: false, modifiers: Modifiers::NONE });
+    h.run_steps(3);
+    let after = margins(&h);
+    assert!((after[0] - want).abs() < 0.03, "{after:?} want left {want}");
+    assert_eq!(after[1..], start_margins[1..]);
+    // One undo step restores it.
+    h.state_mut().run("edit.undo", json!({})).unwrap();
+    h.run_steps(3);
+    assert_eq!(margins(&h), start_margins);
+    // Esc during a drag cancels: nothing is committed.
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let edge = pos2(screen(&g, pg.page_x(0) + pg.margins[0], 0.0).x, ruler_y);
+    h.run_steps(40);
+    mouse(&mut h, Event::PointerMoved(edge));
+    mouse(&mut h, Event::PointerButton { pos: edge, button: PointerButton::Primary, pressed: true, modifiers: Modifiers::NONE });
+    mouse(&mut h, Event::PointerMoved(pos2(edge.x + per_inch, ruler_y)));
+    mouse(&mut h, Event::Key { key: Key::Escape, physical_key: None, pressed: true, repeat: false, modifiers: Modifiers::NONE });
+    mouse(&mut h, Event::PointerButton { pos: edge, button: PointerButton::Primary, pressed: false, modifiers: Modifiers::NONE });
+    h.run_steps(3);
+    assert_eq!(margins(&h), start_margins);
+}
+
+fn press(h: &mut Harness, p: Pos2) {
+    h.run_steps(40);
+    mouse(h, Event::PointerMoved(p));
+    mouse(h, Event::PointerButton { pos: p, button: PointerButton::Primary, pressed: true, modifiers: Modifiers::NONE });
+}
+
+fn release(h: &mut Harness, p: Pos2) {
+    mouse(h, Event::PointerButton { pos: p, button: PointerButton::Primary, pressed: false, modifiers: Modifiers::NONE });
+    h.run_steps(3);
+}
+
+/// Screen pixels per inch of the page.
+fn per_inch(g: &Geo) -> f32 {
+    let pg = g.paper.clone().unwrap();
+    (72.0 / (pg.paper_pt.0 as f64 / pg.page_w)) as f32 * g.z
+}
+
+#[test]
+fn header_and_footer_margins_are_dragged_on_the_vertical_ruler() {
+    let mut h = fixture();
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let start = margins(&h);
+    let ruler_x = h.state().grid.rect.unwrap().left() + 9.0;
+    // Header: distance from the top of the page, 0.2 in further down.
+    let at = pos2(ruler_x, screen(&g, 0.0, pg.page_y(0) + pg.margins[4]).y);
+    let to = pos2(ruler_x, at.y + 0.2 * per_inch(&g));
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(ruler_x, at.y + 4.0)));
+    mouse(&mut h, Event::PointerMoved(to));
+    release(&mut h, to);
+    let after = margins(&h);
+    assert!((after[4] - (start[4] + 0.2)).abs() < 0.03, "{after:?} vs {start:?}");
+    assert_eq!((after[..4].to_vec(), after[5]), (start[..4].to_vec(), start[5]));
+    h.state_mut().run("edit.undo", json!({})).unwrap();
+    h.run_steps(3);
+    assert_eq!(margins(&h), start);
+    // Footer: distance from the bottom, dragged up by 0.2 in grows it (zoom out so the page
+    // bottom is on screen).
+    h.state_mut().run("view.zoom", json!({"percent": 50})).unwrap();
+    h.run_steps(4);
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let (_, py, _, ph) = pg.page_rect(0, 0);
+    let at = pos2(ruler_x, screen(&g, 0.0, py + ph - pg.margins[5]).y);
+    let to = pos2(ruler_x, at.y - 0.2 * per_inch(&g));
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(ruler_x, at.y - 4.0)));
+    mouse(&mut h, Event::PointerMoved(to));
+    release(&mut h, to);
+    assert!((margins(&h)[5] - (start[5] + 0.2)).abs() < 0.03, "{:?}", margins(&h));
+}
+
+#[test]
+fn right_to_left_sheets_mirror_the_horizontal_ruler_drag() {
+    let mut h = fixture_with(true, None);
+    let g = geo(&h);
+    assert!(g.rtl);
+    let pg = g.paper.clone().unwrap();
+    let start = margins(&h);
+    let y = h.state().grid.rect.unwrap().top() + 9.0;
+    // The left margin edge is drawn on the right of the mirrored page; dragging it towards the
+    // page centre (screen-left) grows the left margin.
+    let at = pos2(g.mirror_x(screen(&g, pg.page_x(0) + pg.margins[0], 0.0).x), y);
+    let to = pos2(at.x - per_inch(&g), y);
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(at.x - 4.0, y)));
+    mouse(&mut h, Event::PointerMoved(to));
+    release(&mut h, to);
+    let after = margins(&h);
+    assert!((after[0] - (start[0] + 1.0)).abs() < 0.03, "{after:?} vs {start:?}");
+    assert_eq!(after[1], start[1]);
+}
+
+#[test]
+fn preview_repaginates_so_fit_to_width_matches_the_commit() {
+    let mut h = fixture_with(false, Some(json!({"fitWidth": 1, "fitHeight": 0})));
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let start = margins(&h);
+    let y = h.state().grid.rect.unwrap().top() + 9.0;
+    let at = pos2(screen(&g, pg.page_x(0) + pg.margins[0], 0.0).x, y);
+    let to = pos2(at.x + 2.0 * per_inch(&g), y);
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(at.x + 4.0, y)));
+    mouse(&mut h, Event::PointerMoved(to));
+    h.run_steps(2);
+    let live_scale = geo(&h).paper.unwrap().scale;
+    assert_eq!(margins(&h), start);
+    assert!(live_scale < pg.scale, "live scale {live_scale} should shrink below {}", pg.scale);
+    release(&mut h, to);
+    h.run_steps(2);
+    let committed = geo(&h).paper.unwrap().scale;
+    assert!((committed - live_scale).abs() < 0.01, "committed {committed} vs preview {live_scale}");
+}
+
+#[test]
+fn right_to_left_sheets_carry_the_vertical_ruler_on_the_right() {
+    let mut h = fixture_with(true, None);
+    let g = geo(&h);
+    assert!(g.rtl);
+    let pg = g.paper.clone().unwrap();
+    let start = margins(&h);
+    let outer = h.state().grid.rect.unwrap();
+    // The grid leaves the ruler's width free on the right, not on the left.
+    assert!((g.rect.right() - (outer.right() - gridcraft_ui_egui::paper_view::RULER)).abs() < 0.5, "{:?} {outer:?}", g.rect);
+    assert!((g.rect.left() - outer.left()).abs() < 0.5);
+    let x = outer.right() - 9.0;
+    let at = pos2(x, screen(&g, 0.0, pg.page_y(0) + pg.margins[2]).y);
+    let to = pos2(x, at.y + 0.25 * per_inch(&g));
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(x, at.y + 4.0)));
+    mouse(&mut h, Event::PointerMoved(to));
+    release(&mut h, to);
+    let after = margins(&h);
+    assert!((after[2] - (start[2] + 0.25)).abs() < 0.03, "{after:?} vs {start:?}");
+    // The left ruler strip is not a handle any more: nothing happens there.
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let at = pos2(outer.left() + 9.0, screen(&g, 0.0, pg.page_y(0) + pg.margins[3]).y);
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(at.x, at.y - 30.0)));
+    release(&mut h, pos2(at.x, at.y - 30.0));
+    assert_eq!(margins(&h)[3], start[3]);
+}
+
+#[test]
+fn header_distance_cannot_be_dragged_past_the_top_margin() {
+    let mut h = fixture();
+    let g = geo(&h);
+    let pg = g.paper.clone().unwrap();
+    let start = margins(&h);
+    let ruler_x = h.state().grid.rect.unwrap().left() + 9.0;
+    let at = pos2(ruler_x, screen(&g, 0.0, pg.page_y(0) + pg.margins[4]).y);
+    let to = pos2(ruler_x, at.y + 3.0 * per_inch(&g));
+    press(&mut h, at);
+    mouse(&mut h, Event::PointerMoved(pos2(ruler_x, at.y + 4.0)));
+    mouse(&mut h, Event::PointerMoved(to));
+    release(&mut h, to);
+    let after = margins(&h);
+    assert!((after[4] - start[2]).abs() < 0.011, "header {} should stop at the top margin {}", after[4], start[2]);
+    assert_eq!(after[2], start[2]);
+}
diff --git a/crates/ui-egui/tests/page_setup_margins.rs b/crates/ui-egui/tests/page_setup_margins.rs
new file mode 100644
index 0000000..c604d77
--- /dev/null
+++ b/crates/ui-egui/tests/page_setup_margins.rs
@@ -0,0 +1,42 @@
+//! Page Setup opens on the active sheet's saved margins, so OK without edits keeps them (issue #524).
+
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::SheetApp;
+use serde_json::{Value, json};
+
+fn margins(app: &SheetApp) -> [f32; 6] {
+    app.session.active().and_then(|d| d.wb.active()).map(|s| s.print.margins).unwrap_or_default()
+}
+
+fn app_with_custom_margins() -> SheetApp {
+    let mut session = Session::new();
+    session.new_workbook();
+    let mut app = SheetApp::new(session, Default::default());
+    app.run("pageLayout.margins", json!({"left": 2.0, "right": 2.5, "top": 3.0, "bottom": 0.25, "header": 0.1, "footer": 0.2})).unwrap();
+    assert_eq!(margins(&app), [2.0, 2.5, 3.0, 0.25, 0.1, 0.2]);
+    app
+}
+
+#[test]
+fn page_setup_ok_without_edits_keeps_custom_margins() {
+    // Custom Margins / File > Page Setup open it bare; Print Titles opens it on the Sheet tab.
+    for params in [json!({}), json!({"tab": "Sheet"})] {
+        let mut app = app_with_custom_margins();
+        app.open_dialog("pageSetup", params);
+        let d = app.dialog.take().unwrap();
+        let shown = json!({"left": 2.0, "right": 2.5, "top": 3.0, "bottom": 0.25, "header": 0.1, "footer": 0.2});
+        assert_eq!(Value::Object(d.values.clone()), shown);
+        app.run("pageLayout.margins", Value::Object(d.values)).unwrap();
+        assert_eq!(margins(&app), [2.0, 2.5, 3.0, 0.25, 0.1, 0.2]);
+    }
+}
+
+#[test]
+fn page_setup_one_edited_field_keeps_the_other_margins() {
+    let mut app = app_with_custom_margins();
+    app.open_dialog("pageSetup", json!({}));
+    let mut d = app.dialog.take().unwrap();
+    d.values.insert("left".into(), json!(1.5));
+    app.run("pageLayout.margins", Value::Object(d.values)).unwrap();
+    assert_eq!(margins(&app), [1.5, 2.5, 3.0, 0.25, 0.1, 0.2]);
+}
diff --git a/crates/ui-egui/tests/selection_scroll.rs b/crates/ui-egui/tests/selection_scroll.rs
new file mode 100644
index 0000000..06e0d18
--- /dev/null
+++ b/crates/ui-egui/tests/selection_scroll.rs
@@ -0,0 +1,106 @@
+//! Extending the selection from the keyboard scrolls its moving end into view, not the anchor.
+
+use egui::{Event, Key, Modifiers};
+use gridcraft_engine::Session;
+use gridcraft_engine::core::{CellRef, RangeRef};
+use gridcraft_ui_egui::{SheetApp, grid::Geo};
+use serde_json::json;
+
+type Harness = egui_kittest::Harness<'static, SheetApp>;
+
+/// Ctrl on Windows and Linux sets both `ctrl` and `command`.
+const CTRL: Modifiers = Modifiers { alt: false, ctrl: true, shift: false, mac_cmd: false, command: true };
+const CTRL_SHIFT: Modifiers = Modifiers { shift: true, ..CTRL };
+
+/// Column A filled down to A200 and row 1 filled across to CV1, far past one screen each way.
+fn harness() -> Harness {
+    let mut s = Session::new();
+    s.new_workbook();
+    let down: Vec<Vec<i64>> = (1..=200).map(|r| vec![r]).collect();
+    s.execute("range.setValues", json!({"range": "A1", "values": down})).unwrap();
+    let across: Vec<i64> = (1..=100).collect();
+    s.execute("range.setValues", json!({"range": "A1", "values": [across]})).unwrap();
+    s.execute("selection.set", json!({"cell": "A1"})).unwrap();
+    let mut h = Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            let ctx = ui.ctx().clone();
+            app.logic(&ctx);
+            app.ui(ui);
+        },
+        SheetApp::new(s, Default::default()),
+    );
+    h.run_steps(4);
+    h
+}
+
+fn key(h: &mut Harness, k: Key, m: Modifiers) {
+    h.input_mut().events.push(Event::Key { key: k, physical_key: Some(k), pressed: true, repeat: false, modifiers: m });
+    h.input_mut().events.push(Event::Key { key: k, physical_key: Some(k), pressed: false, repeat: false, modifiers: m });
+    h.run_steps(2);
+}
+
+/// Whether the cell's centre is on screen (a whole cell can sit a few pixels under the edge when
+/// scrolling far down widens the row headings).
+fn visible(h: &Harness, a1: &str) -> bool {
+    let app = h.state();
+    let sheet = app.session.active().unwrap().wb.active().unwrap();
+    let geo = Geo::new(sheet, app.grid.rect.unwrap(), app.view().scroll);
+    geo.cells.contains(geo.cell_rect(sheet, CellRef::parse(a1).unwrap()).center())
+}
+
+fn assert_extended(h: &Harness, anchor: &str, moving_end: &str) {
+    let selection = &h.state().session.active().unwrap().selection;
+    let (anchor_cell, end_cell) = (CellRef::parse(anchor).unwrap(), CellRef::parse(moving_end).unwrap());
+    assert_eq!(selection.current(), RangeRef::new(anchor_cell, end_cell));
+    assert_eq!(selection.anchor, anchor_cell);
+    assert_eq!(selection.active, anchor_cell, "extending keeps the active cell on the anchor");
+    assert!(visible(h, moving_end), "the moving end {moving_end} is scrolled into view");
+}
+
+#[test]
+fn ctrl_shift_arrows_scroll_the_moving_end_into_view() {
+    // Down, then back Up past the top once the view has scrolled.
+    let mut h = harness();
+    key(&mut h, Key::ArrowDown, CTRL_SHIFT);
+    assert_extended(&h, "A1", "A200");
+    assert!(!visible(&h, "A1"), "the view follows the moving end, away from the anchor");
+    let mut h = harness();
+    key(&mut h, Key::ArrowDown, CTRL);
+    assert!(visible(&h, "A200") && !visible(&h, "A1"));
+    key(&mut h, Key::ArrowUp, CTRL_SHIFT);
+    assert_extended(&h, "A200", "A1");
+    // Right, then back Left.
+    let mut h = harness();
+    key(&mut h, Key::ArrowRight, CTRL_SHIFT);
+    assert_extended(&h, "A1", "CV1");
+    let mut h = harness();
+    key(&mut h, Key::ArrowRight, CTRL);
+    assert!(visible(&h, "CV1") && !visible(&h, "A1"));
+    key(&mut h, Key::ArrowLeft, CTRL_SHIFT);
+    assert_extended(&h, "CV1", "A1");
+}
+
+#[test]
+fn shift_arrows_scroll_the_moving_end_into_view() {
+    let mut h = harness();
+    for _ in 0..60 {
+        key(&mut h, Key::ArrowDown, Modifiers::SHIFT);
+    }
+    assert_extended(&h, "A1", "A61");
+    for _ in 0..30 {
+        key(&mut h, Key::ArrowRight, Modifiers::SHIFT);
+    }
+    assert_extended(&h, "A1", "AE61");
+}
+
+#[test]
+fn ctrl_shift_home_and_end_scroll_the_moving_end_into_view() {
+    let mut h = harness();
+    key(&mut h, Key::End, CTRL_SHIFT);
+    assert_extended(&h, "A1", "CV200");
+    let mut h = harness();
+    key(&mut h, Key::End, CTRL);
+    assert!(!visible(&h, "A1"));
+    key(&mut h, Key::Home, CTRL_SHIFT);
+    assert_extended(&h, "CV200", "A1");
+}
diff --git a/crates/ui-egui/tests/sheet_navigator.rs b/crates/ui-egui/tests/sheet_navigator.rs
new file mode 100644
index 0000000..a16e306
--- /dev/null
+++ b/crates/ui-egui/tests/sheet_navigator.rs
@@ -0,0 +1,44 @@
+//! The All Sheets navigator next to the sheet tabs: type part of a name, Enter, and that sheet is active (#839).
+
+use egui::{Event, Key, Modifiers};
+use egui_kittest::kittest::Queryable;
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::SheetApp;
+use serde_json::json;
+
+fn harness() -> egui_kittest::Harness<'static, SheetApp> {
+    let mut s = Session::new();
+    s.new_workbook();
+    for _ in 0..3 {
+        s.run("home.insertSheet", json!({})).unwrap();
+    }
+    for (i, name) in ["Data", "Hidden", "Notes", "Summary"].iter().enumerate() {
+        s.run("sheet.rename", json!({"sheet": i, "name": name})).unwrap();
+    }
+    s.run("sheet.hide", json!({"sheet": 1})).unwrap();
+    s.run("sheet.activate", json!({"sheet": 0})).unwrap();
+    let mut h = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            let ctx = ui.ctx().clone();
+            app.logic(&ctx);
+            app.ui(ui);
+        },
+        SheetApp::new(s, Default::default()),
+    );
+    h.run_steps(4);
+    h
+}
+
+#[test]
+fn typing_a_name_and_enter_activates_that_sheet() {
+    let mut h = harness();
+    assert_eq!(h.state().session.active().unwrap().wb.active_sheet, 0);
+    h.get_by_label("All sheets").click();
+    h.run_steps(4);
+    h.input_mut().events.push(Event::Text("summ".into()));
+    h.run_steps(3);
+    h.input_mut().events.push(Event::Key { key: Key::Enter, physical_key: None, pressed: true, repeat: false, modifiers: Modifiers::NONE });
+    h.input_mut().events.push(Event::Key { key: Key::Enter, physical_key: None, pressed: false, repeat: false, modifiers: Modifiers::NONE });
+    h.run_steps(4);
+    assert_eq!(h.state().session.active().unwrap().wb.active_sheet, 3, "Enter on the filtered row must activate Summary");
+}
diff --git a/crates/ui-egui/tests/sheet_tabs.rs b/crates/ui-egui/tests/sheet_tabs.rs
new file mode 100644
index 0000000..966ea60
--- /dev/null
+++ b/crates/ui-egui/tests/sheet_tabs.rs
@@ -0,0 +1,176 @@
+//! Overflowing worksheet tabs, exercised through their actual painted geometry and input.
+use egui::{Color32, Event, Modifiers, PointerButton, Rect, Shape, pos2, vec2};
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::SheetApp;
+use serde_json::json;
+
+type Harness = egui_kittest::Harness<'static, SheetApp>;
+
+fn harness(width: f32, active: usize) -> Harness {
+    let mut s = Session::new();
+    s.new_workbook();
+    s.execute("sheet.rename", json!({"sheet":0,"name":"Tab00"})).unwrap();
+    for i in 1..30 {
+        s.execute("home.insertSheet", json!({"name":format!("Tab{i:02}")})).unwrap();
+    }
+    s.execute("sheet.activate", json!({"sheet":active})).unwrap();
+    let mut fonts_ready = false;
+    let mut h = Harness::builder().with_step_dt(1.0 / 60.0).with_size(vec2(width, 120.0)).build_ui_state(
+        move |ui, app: &mut SheetApp| {
+            if !fonts_ready {
+                ui.ctx().set_fonts(gridcraft_ui_egui::theme::font_definitions());
+                fonts_ready = true;
+                return;
+            }
+            app.grid.cells_rect = Some(Rect::from_min_size(pos2(0.0, 0.0), vec2(ui.max_rect().width(), 80.0)));
+            gridcraft_ui_egui::tabs::sheet_tabs(app, ui);
+        },
+        SheetApp::new(s, Default::default()),
+    );
+    h.run_steps(20);
+    h
+}
+
+fn tab(h: &Harness, name: &str) -> Option<(Rect, Rect)> {
+    h.output().shapes.iter().find_map(|s| match &s.shape {
+        Shape::Text(t) if t.galley.job.text == name => Some((t.visual_bounding_rect(), s.clip_rect)),
+        _ => None,
+    })
+}
+
+fn assert_visible(h: &Harness, name: &str) {
+    let (text, clip) = tab(h, name).unwrap_or_else(|| panic!("{name} was not painted in the tab viewport"));
+    assert!(clip.contains_rect(text), "{name} is clipped: text={text:?}, viewport={clip:?}");
+}
+
+fn click(h: &mut Harness, at: egui::Pos2) {
+    h.input_mut().events.extend([
+        Event::PointerMoved(at),
+        Event::PointerButton { pos: at, button: PointerButton::Primary, pressed: true, modifiers: Modifiers::NONE },
+    ]);
+    h.step();
+    h.input_mut().events.push(Event::PointerButton { pos: at, button: PointerButton::Primary, pressed: false, modifiers: Modifiers::NONE });
+    h.run_steps(20);
+}
+
+#[test]
+fn opening_and_activating_late_sheets_reveals_their_tabs() {
+    for width in [500.0, 1000.0] {
+        let mut h = harness(width, 29);
+        assert_visible(&h, "Tab29");
+        h.state_mut().run("sheet.activate", json!({"sheet":0})).unwrap();
+        h.run_steps(20);
+        assert_visible(&h, "Tab00");
+        h.state_mut().run("sheet.activate", json!({"sheet":20})).unwrap();
+        h.run_steps(20);
+        assert_visible(&h, "Tab20");
+    }
+}
+
+#[test]
+fn navigation_arrows_reveal_the_selected_tab() {
+    let mut h = harness(700.0, 0);
+    let (_, clip) = tab(&h, "Tab00").unwrap();
+    let next = pos2(clip.left() - 20.0, clip.center().y);
+    for _ in 0..29 {
+        click(&mut h, next);
+    }
+    assert_eq!(h.state().session.doc().unwrap().wb.active_sheet, 29);
+    assert_visible(&h, "Tab29");
+}
+
+#[test]
+fn manual_wheel_and_trackpad_browsing_does_not_change_selection_or_snap_back() {
+    for delta in [vec2(0.0, -350.0), vec2(-350.0, 0.0)] {
+        let mut h = harness(700.0, 0);
+        let before = h.state().session.doc().unwrap().wb.clone();
+        let (_, clip) = tab(&h, "Tab00").unwrap();
+        h.input_mut().events.extend([
+            Event::PointerMoved(clip.center()),
+            Event::MouseWheel {
+                unit: egui::MouseWheelUnit::Point,
+                phase: egui::TouchPhase::Start,
+                delta: vec2(0.0, 0.0),
+                modifiers: Modifiers::NONE,
+            },
+        ]);
+        h.step();
+        h.input_mut().events.push(Event::MouseWheel {
+            unit: egui::MouseWheelUnit::Point,
+            phase: egui::TouchPhase::Move,
+            delta,
+            modifiers: Modifiers::NONE,
+        });
+        h.step();
+        h.input_mut().events.push(Event::MouseWheel {
+            unit: egui::MouseWheelUnit::Point,
+            phase: egui::TouchPhase::End,
+            delta: vec2(0.0, 0.0),
+            modifiers: Modifiers::NONE,
+        });
+        h.run_steps(40);
+        assert!(!tab(&h, "Tab00").is_some_and(|(r, c)| c.contains_rect(r)), "gesture should browse away from the selected tab: {delta:?}");
+        assert_eq!(h.state().session.doc().unwrap().wb, before, "browsing tabs must not edit the workbook");
+        h.run_steps(40);
+        assert!(!tab(&h, "Tab00").is_some_and(|(r, c)| c.contains_rect(r)), "idle frames must not snap back");
+        h.state_mut().run("sheet.activate", json!({"sheet":29})).unwrap();
+        h.run_steps(20);
+        assert_visible(&h, "Tab29");
+    }
+}
+#[test]
+fn hidden_sheets_long_names_and_window_resize_keep_active_tab_visible() {
+    let mut h = harness(1000.0, 0);
+    for sheet in 1..10 {
+        h.state_mut().run("sheet.hide", json!({"sheet":sheet})).unwrap();
+    }
+    let name = "Quarterly results and forecasts";
+    h.state_mut().run("sheet.rename", json!({"sheet":29,"name":name})).unwrap();
+    h.state_mut().run("sheet.activate", json!({"sheet":29})).unwrap();
+    h.run_steps(20);
+    assert_visible(&h, name);
+    h.set_size(vec2(500.0, 120.0));
+    h.run_steps(20);
+    assert_visible(&h, name);
+    h.set_size(vec2(1000.0, 120.0));
+    h.run_steps(20);
+    assert_visible(&h, name);
+    assert_eq!(h.state().session.doc().unwrap().wb.active_sheet, 29);
+}
+
+#[test]
+fn new_sheet_button_stays_reachable_and_reveals_the_inserted_tab() {
+    let mut h = harness(700.0, 29);
+    let (_, clip) = tab(&h, "Tab29").unwrap();
+    click(&mut h, pos2(clip.right() + 18.0, clip.center().y));
+    let d = h.state().session.doc().unwrap();
+    assert_eq!(d.wb.sheets.len(), 31);
+    let name = d.wb.active().unwrap().name.clone();
+    assert_visible(&h, &name);
+}
+
+#[test]
+fn overflow_leaves_the_worksheet_scrollbar_reachable() {
+    for width in [500.0, 700.0, 1200.0] {
+        let mut h = harness(width, 0);
+        let (bar, clip) = h
+            .output()
+            .shapes
+            .iter()
+            .find_map(|s| match &s.shape {
+                Shape::Rect(r) if r.fill == Color32::from_gray(190) && r.rect.height() == 8.0 => Some((r.rect, s.clip_rect)),
+                _ => None,
+            })
+            .expect("worksheet scrollbar thumb must be painted");
+        assert!(clip.contains_rect(bar), "worksheet scrollbar is offscreen: {bar:?}, {clip:?}");
+        let at = bar.center();
+        h.input_mut().events.extend([
+            Event::PointerMoved(at),
+            Event::PointerButton { pos: at, button: PointerButton::Primary, pressed: true, modifiers: Modifiers::NONE },
+        ]);
+        h.step();
+        h.input_mut().events.push(Event::PointerMoved(at + vec2(12.0, 0.0)));
+        h.step();
+        assert!(h.state().view().scroll.x > 0.0, "worksheet scrollbar must respond to dragging");
+    }
+}
diff --git a/crates/ui-egui/tests/validation_input_message.rs b/crates/ui-egui/tests/validation_input_message.rs
new file mode 100644
index 0000000..e05dbce
--- /dev/null
+++ b/crates/ui-egui/tests/validation_input_message.rs
@@ -0,0 +1,56 @@
+//! A list validation's input message must not cover the dropdown it describes (#505).
+
+use egui::{Event, Key, Modifiers, PointerButton};
+use egui_kittest::kittest::Queryable;
+use gridcraft_engine::Session;
+use gridcraft_engine::core::CellRef;
+use gridcraft_ui_egui::{SheetApp, grid};
+use serde_json::json;
+
+type Harness = egui_kittest::Harness<'static, SheetApp>;
+
+const MESSAGE: &str = "Pick a colour from the list";
+
+fn harness() -> Harness {
+    let mut session = Session::new();
+    session.new_workbook();
+    session.execute("data.validation", json!({"range": "B2", "type": "list", "formula1": "\"Red,Green,Blue\"", "inputMessage": MESSAGE})).unwrap();
+    session.execute("selection.set", json!({"cell": "B2"})).unwrap();
+    let mut h = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            app.logic(ui.ctx());
+            app.ui(ui);
+        },
+        SheetApp::new(session, Default::default()),
+    );
+    h.run_steps(4);
+    h
+}
+
+fn message_shown(h: &Harness) -> bool {
+    h.query_by_label(MESSAGE).is_some()
+}
+
+#[test]
+fn input_message_hides_while_the_list_is_open() {
+    let mut h = harness();
+    assert!(message_shown(&h), "the selected cell's input message is shown");
+
+    let app = h.state();
+    let sh = app.session.active().unwrap().wb.active().unwrap();
+    let geo = grid::Geo::new(sh, app.grid.rect.unwrap(), app.view().scroll);
+    let pos = grid::validation_arrow(sh, &geo, CellRef::parse("B2").unwrap()).unwrap().center();
+    h.input_mut().events.push(Event::PointerMoved(pos));
+    h.input_mut().events.push(Event::PointerButton { pos, button: PointerButton::Primary, pressed: true, modifiers: Modifiers::NONE });
+    h.input_mut().events.push(Event::PointerButton { pos, button: PointerButton::Primary, pressed: false, modifiers: Modifiers::NONE });
+    h.run_steps(2);
+
+    assert!(h.state().grid.list_picker.is_some(), "the dropdown arrow opens the list");
+    assert!(h.query_by_label("Green").is_some(), "the list shows its items");
+    assert!(!message_shown(&h), "the input message must not cover the open list");
+
+    h.input_mut().events.push(Event::Key { key: Key::Escape, physical_key: None, pressed: true, repeat: false, modifiers: Modifiers::NONE });
+    h.run_steps(2);
+    assert!(h.state().grid.list_picker.is_none(), "Escape closes the list");
+    assert!(message_shown(&h), "the input message comes back once the list is closed");
+}
diff --git a/crates/ui-egui/tests/zoom_dialog.rs b/crates/ui-egui/tests/zoom_dialog.rs
new file mode 100644
index 0000000..f5be908
--- /dev/null
+++ b/crates/ui-egui/tests/zoom_dialog.rs
@@ -0,0 +1,85 @@
+//! The Zoom dialog stores the Magnification the user picks.
+
+use egui::vec2;
+use egui_kittest::kittest::Queryable;
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::SheetApp;
+use gridcraft_ui_egui::control::{Outcome, handle};
+use serde_json::{Value as Json, json};
+
+fn harness() -> egui_kittest::Harness<'static, SheetApp> {
+    let mut session = Session::new();
+    session.new_workbook();
+    let mut h = egui_kittest::Harness::builder().with_size(vec2(1200.0, 800.0)).build_ui_state(
+        |ui, app: &mut SheetApp| {
+            app.logic(&ui.ctx().clone());
+            app.ui(ui);
+        },
+        SheetApp::new(session, Default::default()),
+    );
+    h.run_steps(6);
+    h
+}
+
+fn zoom(h: &egui_kittest::Harness<'static, SheetApp>) -> u16 {
+    h.state().session.active().unwrap().wb.active().unwrap().zoom
+}
+
+fn control(h: &mut egui_kittest::Harness<'static, SheetApp>, method: &str, params: Json) -> Json {
+    let ctx = h.ctx.clone();
+    match handle(h.state_mut(), &ctx, method, &params) {
+        Outcome::Done(v) => v,
+        Outcome::Screenshot { .. } => json!(null),
+    }
+}
+
+#[test]
+fn choosing_a_magnification_and_pressing_ok_sets_that_zoom() {
+    let mut h = harness();
+    h.state_mut().run("view.zoom", json!({"percent": 160})).unwrap();
+    h.state_mut().open_dialog("zoom", json!({}));
+    h.run_steps(6);
+    h.get_by_label("50%").click();
+    h.run_steps(6);
+    h.get_by_label("   OK   ").click();
+    h.run_steps(6);
+    assert!(h.state().dialog.is_none());
+    assert_eq!(zoom(&h), 50);
+}
+
+#[test]
+fn choosing_a_magnification_and_confirming_by_command_sets_that_zoom() {
+    let mut h = harness();
+    h.state_mut().run("view.zoom", json!({"percent": 180})).unwrap();
+    h.state_mut().open_dialog("zoom", json!({}));
+    h.run_steps(6);
+    h.get_by_label("75%").click();
+    h.run_steps(6);
+    let r = control(&mut h, "ui.dialog.confirm", json!({}));
+    assert_eq!(r["ok"], json!(true), "{r}");
+    assert_eq!(zoom(&h), 75);
+}
+
+#[test]
+fn setting_the_magnification_over_the_control_channel_sets_that_zoom() {
+    let mut h = harness();
+    h.state_mut().run("view.zoom", json!({"percent": 180})).unwrap();
+    control(&mut h, "ui.dialog", json!({"name": "zoom"}));
+    control(&mut h, "ui.dialog.set", json!({"field": "preset", "value": "25"}));
+    let r = control(&mut h, "ui.dialog.confirm", json!({}));
+    assert_eq!(r["ok"], json!(true), "{r}");
+    assert_eq!(zoom(&h), 25);
+}
+
+#[test]
+fn a_custom_percentage_after_a_magnification_wins_and_an_unedited_ok_keeps_the_zoom() {
+    let mut h = harness();
+    control(&mut h, "ui.dialog", json!({"name": "zoom"}));
+    control(&mut h, "ui.dialog.set", json!({"field": "preset", "value": "25"}));
+    control(&mut h, "ui.dialog.set", json!({"field": "percent", "value": 225}));
+    control(&mut h, "ui.dialog.confirm", json!({}));
+    assert_eq!(zoom(&h), 225);
+    control(&mut h, "ui.dialog", json!({"name": "zoom"}));
+    control(&mut h, "ui.dialog.confirm", json!({}));
+    assert_eq!(zoom(&h), 225);
+}
diff --git a/crates/xlsx/src/cfb.rs b/crates/xlsx/src/cfb.rs
index 3a74718..5f85e43 100644
--- a/crates/xlsx/src/cfb.rs
+++ b/crates/xlsx/src/cfb.rs
@@ -209,13 +209,19 @@ impl<'a> Compound<'a> {
     }
 
     /// Follows a FAT chain from `start`, reading at most `limit` bytes. A chain longer than the
-    /// FAT (so a cycle) or pointing outside the file is an error.
+    /// FAT (so a cycle) or pointing outside the file is an error. The file may end inside the
+    /// chain's last sector (some writers don't pad it, and Excel opens those files): that sector
+    /// reads short, and the caller checks the stream's declared size against what was read.
     fn read_chain(&self, start: u32, limit: u64) -> Result<Vec<u8>, String> {
         let limit = usize::try_from(limit.min(MAX_STREAM)).unwrap_or(usize::MAX);
         let mut out = Vec::new();
         let mut id = start;
         let mut seen = vec![false; self.fat.len()];
+        let mut cut = false;
         while id != END_OF_CHAIN && out.len() < limit {
+            if cut {
+                return Err("damaged compound file: sector out of range (the file may be truncated)".into());
+            }
             if id >= MAX_REG_SECT {
                 return Err("damaged compound file: broken sector chain".into());
             }
@@ -226,20 +232,26 @@ impl<'a> Compound<'a> {
             }
             let start = (id as usize).checked_add(1).and_then(|i| i.checked_mul(self.sector_size));
             let s = start
-                .and_then(|s| self.bytes.get(s..s.checked_add(self.sector_size)?))
+                .and_then(|s| self.bytes.get(s..s.checked_add(self.sector_size)?.min(self.bytes.len())))
                 .ok_or("damaged compound file: sector out of range (the file may be truncated)")?;
+            cut = s.len() < self.sector_size;
             out.extend_from_slice(s);
             id = *self.fat.get(id as usize).ok_or("damaged compound file: sector missing from the FAT")?;
         }
         Ok(out)
     }
 
-    /// Follows a mini FAT chain inside the mini stream container.
+    /// Follows a mini FAT chain inside the mini stream container. Like `read_chain`, the
+    /// container may end inside the chain's last mini sector.
     fn read_mini_chain(&self, container: &[u8], start: u32, limit: usize) -> Result<Vec<u8>, String> {
         let mut out = Vec::new();
         let mut id = start;
         let mut seen = vec![false; self.mini_fat.len()];
+        let mut cut = false;
         while id != END_OF_CHAIN && out.len() < limit {
+            if cut {
+                return Err("damaged compound file: mini sector out of range".into());
+            }
             if id >= MAX_REG_SECT {
                 return Err("damaged compound file: broken mini sector chain".into());
             }
@@ -249,8 +261,10 @@ impl<'a> Compound<'a> {
                 None => return Err("damaged compound file: mini sector missing from the mini FAT".into()),
             }
             let at = (id as usize).checked_mul(self.mini_sector_size);
-            let s =
-                at.and_then(|a| container.get(a..a.checked_add(self.mini_sector_size)?)).ok_or("damaged compound file: mini sector out of range")?;
+            let s = at
+                .and_then(|a| container.get(a..a.checked_add(self.mini_sector_size)?.min(container.len())))
+                .ok_or("damaged compound file: mini sector out of range")?;
+            cut = s.len() < self.mini_sector_size;
             out.extend_from_slice(s);
             id = *self.mini_fat.get(id as usize).ok_or("damaged compound file: mini sector missing from the mini FAT")?;
         }
@@ -379,4 +393,63 @@ pub(crate) mod tests {
         b[516..520].copy_from_slice(&1u32.to_le_bytes());
         assert!(!is_encrypted(&b));
     }
+
+    /// `compound_file` with one regular-sector stream of `len` bytes (FAT in sector 0, directory
+    /// in sector 1, the stream from sector 2), cut right after the stream's last byte, the way
+    /// some writers leave the final sector unpadded.
+    fn unpadded(len: usize) -> (Vec<u8>, Vec<u8>) {
+        let data: Vec<u8> = (0..len).map(|i| (i % 251) as u8).collect();
+        let mut file = crate::testing::compound_file(&[("Workbook", &data)]);
+        file.truncate(512 * 3 + len);
+        (file, data)
+    }
+
+    #[test]
+    fn an_unpadded_last_sector_still_reads() {
+        let (file, data) = unpadded(5000);
+        assert_ne!(file.len() % 512, 0);
+        let cf = Compound::open(&file).unwrap();
+        assert_eq!(cf.root_stream("Workbook").unwrap().unwrap(), data);
+        // Bytes the stream needs that the file doesn't hold are still damage.
+        let cf = Compound::open(&file[..file.len() - 1]).unwrap();
+        assert!(cf.root_stream("Workbook").is_err());
+    }
+
+    #[test]
+    fn an_unpadded_last_mini_sector_still_reads() {
+        let data: Vec<u8> = (0..1000u32).map(|i| (i % 251) as u8).collect();
+        let mut file = crate::testing::compound_file(&[("Workbook", &data)]);
+        // Header, FAT, directory, mini FAT, then the mini stream holding the stream's bytes.
+        file.truncate(512 * 4 + data.len());
+        let cf = Compound::open(&file).unwrap();
+        assert_eq!(cf.root_stream("Workbook").unwrap().unwrap(), data);
+        let cf = Compound::open(&file[..file.len() - 1]).unwrap();
+        assert!(cf.root_stream("Workbook").is_err());
+    }
+
+    #[test]
+    fn a_cut_sector_inside_a_chain_is_damage() {
+        let (mut file, _) = unpadded(5000);
+        // The cut sector (11) points on to the directory sector and the stream claims those
+        // bytes too: the partial sector would splice 392 bytes into the middle of the stream.
+        file[512 + 11 * 4..512 + 12 * 4].copy_from_slice(&1u32.to_le_bytes());
+        file[1024 + 128 + 120..1024 + 128 + 124].copy_from_slice(&5512u32.to_le_bytes());
+        let cf = Compound::open(&file).unwrap();
+        assert!(cf.root_stream("Workbook").is_err());
+    }
+
+    #[test]
+    fn a_cut_mini_sector_inside_a_chain_is_damage() {
+        let small = [7u8; 100];
+        let data: Vec<u8> = (0..1000u32).map(|i| (i % 251) as u8).collect();
+        let mut file = crate::testing::compound_file(&[("Small", &small), ("Workbook", &data)]);
+        // "Small" holds mini sectors 0-1, "Workbook" 2-17; the mini stream starts at sector 3.
+        file.truncate(512 * 4 + 128 + data.len());
+        assert_eq!(Compound::open(&file).unwrap().root_stream("Workbook").unwrap().unwrap(), data);
+        // The cut mini sector (17) points on to sector 0 and the stream claims those bytes too.
+        file[1536 + 17 * 4..1536 + 18 * 4].copy_from_slice(&0u32.to_le_bytes());
+        file[1024 + 2 * 128 + 120..1024 + 2 * 128 + 124].copy_from_slice(&1064u32.to_le_bytes());
+        let cf = Compound::open(&file).unwrap();
+        assert!(cf.root_stream("Workbook").is_err());
+    }
 }
diff --git a/crates/xlsx/src/chart.rs b/crates/xlsx/src/chart.rs
index 052d620..dee33c8 100644
--- a/crates/xlsx/src/chart.rs
+++ b/crates/xlsx/src/chart.rs
@@ -106,7 +106,7 @@ fn read_series(s: &El) -> Series {
         color,
         secondary: false,
         kind: None,
-        smooth: s.child("smooth").and_then(|e| e.attr("val")).and_then(|v| v.parse::<u8>().ok()).is_some_and(|v| v != 0),
+        smooth: bool_val(s, "smooth"),
         trendlines: s.kids("trendline").filter_map(read_trendline).collect(),
     }
 }
@@ -201,7 +201,7 @@ pub fn read_chart(root: &El) -> Option<Chart> {
         }
     }
     let kind = if groups.len() > 1 { ChartKind::Combo } else { first_kind };
-    let show_val = |e: &El| e.child("dLbls").and_then(|d| d.child_val("showVal")).is_some_and(|v| v == "1" || v == "true");
+    let show_val = |e: &El| e.child("dLbls").is_some_and(|d| bool_val(d, "showVal"));
     let data_labels = groups.iter().any(|(g, _)| show_val(g) || g.kids("ser").any(show_val));
     let val_axes: Vec<&El> = plot.kids("valAx").collect();
     let cat_ax = plot.child("catAx").or_else(|| plot.child("dateAx"));
@@ -336,10 +336,46 @@ fn num_data(tag: &str, f: Option<&str>, wb: &Workbook, si: usize) -> String {
     s
 }
 
+/// Splits the inside of an array constant on `,` and `;` outside double quotes; inside quotes `""` is a literal quote.
+/// Unquoted items are trimmed; quoted ones keep the text between the quotes and drop the spaces around them.
+fn split_array_items(inner: &str) -> Vec<String> {
+    let mut items = Vec::new();
+    let mut cur = String::new();
+    let mut quoted = false;
+    let mut in_quote = false;
+    let mut chars = inner.chars().peekable();
+    let finish = |cur: &mut String, quoted: &mut bool| {
+        let text = std::mem::take(cur);
+        let item = if *quoted { text } else { text.trim().to_string() };
+        *quoted = false;
+        item
+    };
+    while let Some(c) = chars.next() {
+        match c {
+            '"' if in_quote && chars.peek() == Some(&'"') => {
+                cur.push('"');
+                chars.next();
+            }
+            '"' => {
+                if !quoted && cur.trim().is_empty() {
+                    cur.clear();
+                }
+                in_quote = !in_quote;
+                quoted = true;
+            }
+            ',' | ';' if !in_quote => items.push(finish(&mut cur, &mut quoted)),
+            c if quoted && !in_quote && c.is_whitespace() => {}
+            _ => cur.push(c),
+        }
+    }
+    items.push(finish(&mut cur, &mut quoted));
+    items
+}
+
 fn str_data(tag: &str, f: &str, wb: &Workbook, si: usize) -> String {
     let f = f.trim();
     if f.starts_with('{') {
-        let vals: Vec<String> = f.trim_matches(|c| c == '{' || c == '}').split([',', ';']).map(|v| v.trim().trim_matches('"').to_string()).collect();
+        let vals = split_array_items(f.trim_matches(|c| c == '{' || c == '}'));
         let mut s = format!("<c:{tag}><c:strLit><c:ptCount val=\"{}\"/>", vals.len());
         for (i, v) in vals.iter().enumerate() {
             let _ = write!(s, "<c:pt idx=\"{i}\"><c:v>{}</c:v></c:pt>", esc(v));
diff --git a/crates/xlsx/src/drawing.rs b/crates/xlsx/src/drawing.rs
index 076148a..6dbd17e 100644
--- a/crates/xlsx/src/drawing.rs
+++ b/crates/xlsx/src/drawing.rs
@@ -11,6 +11,8 @@ use crate::read::Ctx;
 use crate::tables::EMU_PER_PX;
 use crate::xml::{El, esc, esc_attr};
 
+mod ink;
+
 // ---------------------------------------------------------------- reading
 
 fn emu_px(v: Option<i64>) -> f32 {
@@ -195,6 +197,9 @@ pub fn read_drawing(cx: &mut Ctx<'_>, part: &str, sheet: &mut Sheet) -> Result<(
 
 fn read_shape(obj: &El, anchor: Anchor) -> Option<Shape> {
     let sp = obj.child("spPr")?;
+    if let Some(shape) = ink::read(obj, anchor) {
+        return Some(shape);
+    }
     let prst = sp.child("prstGeom").and_then(|g| g.attr("prst")).unwrap_or("rect");
     let tx_box = obj.path(&["nvSpPr", "cNvSpPr"]).is_some_and(|c| c.flag("txBox", false));
     let ln = sp.child("ln");
@@ -358,6 +363,12 @@ pub fn write_drawing(sheet: &Sheet, theme: &Theme, objs: &[Obj<'_>]) -> String {
                 let (open, close) = anchor_open(sheet, &sh.anchor);
                 close_tag = close;
                 s.push_str(&open);
+                if let Some(xml) = ink::write(sh, theme, id) {
+                    s.push_str(&xml);
+                    s.push_str("<xdr:clientData/>");
+                    s.push_str(close_tag);
+                    continue;
+                }
                 let (prst, tx) = match sh.kind {
                     ShapeKind::Rectangle => ("rect", false),
                     ShapeKind::RoundedRectangle => ("roundRect", false),
diff --git a/crates/xlsx/src/drawing/ink.rs b/crates/xlsx/src/drawing/ink.rs
new file mode 100644
index 0000000..b48d99e
--- /dev/null
+++ b/crates/xlsx/src/drawing/ink.rs
@@ -0,0 +1,207 @@
+//! The open, solid polylines the model can represent as editable ink. This is DrawingML
+//! geometry, not Office InkML. Unsupported geometry keeps the existing shape-import fallback.
+
+use super::*;
+
+const MAX_POINTS: usize = 20_000;
+const MAX_COORD: f64 = 1e7;
+
+fn bounded(v: f64) -> bool {
+    v.is_finite() && v.abs() <= MAX_COORD
+}
+
+fn only_children(e: &El, names: &[&str]) -> bool {
+    e.children.iter().all(|c| names.contains(&c.name.as_str()))
+}
+
+fn only_attrs(e: &El, names: &[&str]) -> bool {
+    e.attrs.iter().all(|(k, _)| names.contains(&k.as_str()))
+}
+
+fn one<'a>(e: &'a El, name: &str) -> Option<&'a El> {
+    let mut found = e.children.iter().filter(|c| c.name == name);
+    let first = found.next()?;
+    found.next().is_none().then_some(first)
+}
+
+/// Do not partially import a path: losing a curve, subpath, transform or line effect changes
+/// the drawing. Accept only the explicit subset emitted below, including its line styling.
+pub(super) fn read(obj: &El, anchor: Anchor) -> Option<Shape> {
+    if obj.name != "sp"
+        || !only_children(obj, &["nvSpPr", "spPr"])
+        || !only_attrs(obj, &["macro", "textlink"])
+        || obj.attrs.iter().any(|(_, v)| !v.is_empty())
+        || obj.path(&["nvSpPr", "cNvSpPr"]).is_some_and(|e| e.flag("txBox", false))
+    {
+        return None;
+    }
+    let sp = one(obj, "spPr")?;
+    if !only_children(sp, &["xfrm", "custGeom", "noFill", "ln"]) || !sp.attrs.is_empty() {
+        return None;
+    }
+    let no_fill = one(sp, "noFill")?;
+    if !no_fill.attrs.is_empty() || !no_fill.children.is_empty() {
+        return None;
+    }
+    let xf = one(sp, "xfrm")?;
+    if !xf.attrs.is_empty() || !only_children(xf, &["off", "ext"]) {
+        return None;
+    }
+    let off = one(xf, "off")?;
+    if off.attr_i64("x")? != 0 || off.attr_i64("y")? != 0 {
+        return None;
+    }
+    let ext = one(xf, "ext")?;
+    let ew = ext.attr_i64("cx")?;
+    let eh = ext.attr_i64("cy")?;
+    if ew <= 0 || eh <= 0 || anchor.width <= 0.0 || anchor.height <= 0.0 || !bounded(anchor.width as f64) || !bounded(anchor.height as f64) {
+        return None;
+    }
+    let same_extent =
+        |emu: i64, extent: f32| (emu as f64 / EMU_PER_PX - extent as f64).abs() <= 0.001_f64.max(extent as f64 * f32::EPSILON as f64 * 2.0);
+    if !same_extent(ew, anchor.width) || !same_extent(eh, anchor.height) {
+        return None;
+    }
+    let geom = one(sp, "custGeom")?;
+    if !geom.attrs.is_empty() || !only_children(geom, &["avLst", "gdLst", "ahLst", "cxnLst", "rect", "pathLst"]) {
+        return None;
+    }
+    // Text bounds have no effect on this unfilled geometry, which has no caption.
+    if geom.children.iter().any(|c| !matches!(c.name.as_str(), "pathLst" | "rect") && (!c.children.is_empty() || !c.attrs.is_empty())) {
+        return None;
+    }
+    if geom.kids("rect").count() > 1 || geom.kids("rect").any(|r| !r.children.is_empty() || !only_attrs(r, &["l", "t", "r", "b"])) {
+        return None;
+    }
+    let paths = one(geom, "pathLst")?;
+    if paths.children.len() != 1 {
+        return None;
+    }
+    let path = one(paths, "path")?;
+    let w = path.attr_i64("w")?;
+    let h = path.attr_i64("h")?;
+    if w <= 0
+        || h <= 0
+        || path.attr("fill") != Some("none")
+        || !only_attrs(path, &["w", "h", "fill", "stroke", "extrusionOk"])
+        || path.attr("stroke").is_some_and(|_| path.attr_bool("stroke") != Some(true))
+        || path.attr("extrusionOk").is_some_and(|_| path.attr_bool("extrusionOk") != Some(false))
+        || !(2..=MAX_POINTS).contains(&path.children.len())
+    {
+        return None;
+    }
+    let ln = one(sp, "ln")?;
+    if !only_attrs(ln, &["w", "cap", "cmpd", "algn"])
+        || ln.attr("cap") != Some("flat")
+        || ln.attr("cmpd").is_some_and(|v| v != "sng")
+        || ln.attr("algn").is_some_and(|v| v != "ctr")
+        || !only_children(ln, &["solidFill", "miter"])
+    {
+        return None;
+    }
+    let width_emu = ln.attr_i64("w")?;
+    let unit = EMU_PER_PX as i64;
+    if width_emu % unit != 0 || !(1..=40).contains(&(width_emu / unit)) {
+        return None;
+    }
+    let width = width_emu / unit;
+    let join = one(ln, "miter")?;
+    if !join.attrs.is_empty() || !join.children.is_empty() {
+        return None;
+    }
+    let fill = one(ln, "solidFill")?;
+    if fill.children.len() != 1 {
+        return None;
+    }
+    let color = one(fill, "srgbClr")?;
+    if !only_attrs(color, &["val"]) || !only_children(color, &["alpha"]) {
+        return None;
+    }
+    let expected_alpha = if width > 8 { 45_000 } else { 100_000 };
+    if color.children.is_empty() {
+        if expected_alpha != 100_000 {
+            return None;
+        }
+    } else {
+        let alpha = one(color, "alpha")?;
+        if !only_attrs(alpha, &["val"]) || !alpha.children.is_empty() || alpha.attr_i64("val")? != expected_alpha {
+            return None;
+        }
+    }
+    let line = Color::from_hex(color.attr("val")?)?;
+    let mut text = String::new();
+    for (i, command) in path.children.iter().enumerate() {
+        if command.name != if i == 0 { "moveTo" } else { "lnTo" } || !command.attrs.is_empty() || command.children.len() != 1 {
+            return None;
+        }
+        let pt = one(command, "pt")?;
+        if !only_attrs(pt, &["x", "y"]) || !pt.children.is_empty() {
+            return None;
+        }
+        let x = pt.attr_i64("x")? as f64 * anchor.width as f64 / w as f64;
+        let y = pt.attr_i64("y")? as f64 * anchor.height as f64 / h as f64;
+        if !bounded(x) || !bounded(y) {
+            return None;
+        }
+        if i != 0 {
+            text.push(';');
+        }
+        let _ = write!(text, "{},{}", x as f32, y as f32);
+    }
+    Some(Shape { id: 0, kind: ShapeKind::Ink, anchor, fill: Color::Rgb((width as u32) << 16), line, text, format: Default::default() })
+}
+
+/// Invalid/native out-of-range data uses the existing rectangle fallback. A successful
+/// result is complete before it is appended, so malformed points never yield half a stroke.
+pub(super) fn write(shape: &Shape, theme: &Theme, id: usize) -> Option<String> {
+    if shape.kind != ShapeKind::Ink || shape.format.no_line {
+        return None;
+    }
+    let width = match shape.fill {
+        Color::Rgb(rgb) => ((rgb >> 16) & 0xff).max(1),
+        _ => 2,
+    };
+    if !(1..=40).contains(&width) {
+        return None;
+    }
+    let a = &shape.anchor;
+    if !bounded(a.width as f64) || !bounded(a.height as f64) || a.width <= 0.0 || a.height <= 0.0 || !a.dx.is_finite() || !a.dy.is_finite() {
+        return None;
+    }
+    let w = (a.width as f64 * EMU_PER_PX).round().max(1.0) as i64;
+    let h = (a.height as f64 * EMU_PER_PX).round().max(1.0) as i64;
+    let mut points = Vec::new();
+    for point in shape.text.split(';') {
+        if points.len() == MAX_POINTS {
+            return None;
+        }
+        let (x, y) = point.split_once(',')?;
+        let (x, y) = (x.parse::<f64>().ok()?, y.parse::<f64>().ok()?);
+        if !bounded(x) || !bounded(y) {
+            return None;
+        }
+        points.push(((x * EMU_PER_PX).round() as i64, (y * EMU_PER_PX).round() as i64));
+    }
+    if points.len() < 2 {
+        return None;
+    }
+    let [r, g, b] = shape.line.resolve(theme)?;
+    let mut xml = format!(
+        "<xdr:sp macro=\"\" textlink=\"\"><xdr:nvSpPr><xdr:cNvPr id=\"{id}\" name=\"Ink {id}\"/><xdr:cNvSpPr/></xdr:nvSpPr><xdr:spPr>{}<a:custGeom><a:avLst/><a:gdLst/><a:ahLst/><a:cxnLst/><a:pathLst><a:path w=\"{w}\" h=\"{h}\" fill=\"none\">",
+        xfrm(a, "a:xfrm")
+    );
+    for (i, (x, y)) in points.iter().enumerate() {
+        let tag = if i == 0 { "moveTo" } else { "lnTo" };
+        let _ = write!(xml, "<a:{tag}><a:pt x=\"{x}\" y=\"{y}\"/></a:{tag}>");
+    }
+    let _ = write!(
+        xml,
+        "</a:path></a:pathLst></a:custGeom><a:noFill/><a:ln w=\"{}\" cap=\"flat\"><a:solidFill><a:srgbClr val=\"{r:02X}{g:02X}{b:02X}\">",
+        width as i64 * EMU_PER_PX as i64
+    );
+    if width > 8 {
+        xml.push_str("<a:alpha val=\"45000\"/>");
+    }
+    xml.push_str("</a:srgbClr></a:solidFill><a:miter/></a:ln></xdr:spPr></xdr:sp>");
+    Some(xml)
+}
diff --git a/crates/xlsx/src/fmla.rs b/crates/xlsx/src/fmla.rs
index 459364e..ef26387 100644
--- a/crates/xlsx/src/fmla.rs
+++ b/crates/xlsx/src/fmla.rs
@@ -82,6 +82,9 @@ fn expr_to_file(e: Expr) -> String {
         Expr::Unary(gridcraft_formula::UnOp::Spill, r) => Expr::Call("_xlfn.ANCHORARRAY".into(), vec![*r]),
         // Nor an `@` operator: Excel writes `@x` as `_xlfn.SINGLE(x)`.
         Expr::Unary(gridcraft_formula::UnOp::At, x) => Expr::Call("_xlfn.SINGLE".into(), vec![*x]),
+        // Nor the `[@Col]` shorthand: files spell it `[[#This Row],[Col]]`, or Excel repairs
+        // the file and drops the table. Carried as a name, which prints verbatim.
+        Expr::Struct(st) => Expr::Name(gridcraft_formula::printer::struct_ref_file(&st)),
         // Nor trim-reference operators: written as the equivalent `TRIMRANGE(range,n,n)`, which
         // every Excel with trim references reads. (Excel's own file spelling of `A1:.E10` is
         // not publicly documented; the `_xlfn._TRO_*` call forms are accepted on read.)
@@ -152,6 +155,20 @@ mod tests {
         assert_eq!(from_file("Sales[[#This Row],Units]*[[#This Row],Price]"), "Sales[@Units]*[@Price]");
     }
 
+    #[test]
+    fn this_row_long_form() {
+        // `[@Col]` is only Excel's display shorthand; a file holding it is repaired by Excel,
+        // which drops the table.
+        assert_eq!(to_file(&Formula::new("Sales[@Units]*Sales[@[Unit Price]]")), "Sales[[#This Row],[Units]]*Sales[[#This Row],[Unit Price]]");
+        assert_eq!(text_to_file("=[@Units]&COUNTA(Sales[@])"), "[[#This Row],[Units]]&COUNTA(Sales[#This Row])");
+        assert_eq!(text_to_file("=SUM(Sales[Units])+[#Totals]"), "SUM(Sales[Units])+[#Totals]");
+        for f in ["Sales[@Units]*[@[Unit Price]]", "Sales[@]", "[@[Unit Price]]+1"] {
+            let file = to_file(&Formula::new(f));
+            assert!(!file.contains("[@"), "{file}");
+            assert_eq!(from_file(&file), f);
+        }
+    }
+
     #[test]
     fn prefixes() {
         assert_eq!(to_file(&Formula::new("XLOOKUP(1,A:A,B:B)+SUM(A1)")), "_xlfn.XLOOKUP(1,A:A,B:B)+SUM(A1)");
diff --git a/crates/xlsx/src/passthrough.rs b/crates/xlsx/src/passthrough.rs
index f121977..7db21fd 100644
--- a/crates/xlsx/src/passthrough.rs
+++ b/crates/xlsx/src/passthrough.rs
@@ -6,7 +6,8 @@
 //! their `<externalReferences>`, data connections) and each sheet (query tables, form controls,
 //! ActiveX controls, OLE objects, the sheet background and printer settings, with the sheet's
 //! `<picture>`, `<oleObjects>` and `<controls>` XML, the `r:id` of `<pageSetup>` and the legacy
-//! VML shapes those controls need).
+//! VML shapes those controls need). The workbook also keeps its `<fileVersion>` and the
+//! calcFeatures extension, which Excel needs to trust the saved values.
 //!
 //! On write, kept parts get fresh part names where needed and new relationship ids; the `r:id`s in
 //! kept XML are rewritten to match. Kept content is conservative:
@@ -83,6 +84,11 @@ const WORKBOOK_ROOTS: &[&str] = &["customXml", "connections"];
 const SHEET_ROOTS: &[&str] = &["queryTable"];
 /// Sheet relationship kinds that mean the sheet XML may hold elements worth keeping.
 const SHEET_ELEMENT_KINDS: &[&str] = &["oleObject", "ctrlProp", "control", "image", "package", "printerSettings"];
+/// Attributes of `<fileVersion>` (CT_FileVersion).
+const FILE_VERSION_ATTRS: &[&str] = &["appName", "lastEdited", "lowestEdited", "rupBuild", "codeName"];
+/// The workbook extension listing the calculation features the saved values were computed with.
+const CALC_FEATURES_URI: &str = "{B58B0392-4F1F-4190-BB64-5DF3571DCE5F}";
+const NS_CALC_FEATURES: &str = "http://schemas.microsoft.com/office/spreadsheetml/2018/calcfeatures";
 /// Kept sheet elements, in schema order (all after `<legacyDrawing>`, before `<tableParts>`).
 const SHEET_SLOTS: &[&str] = &["picture", "oleObjects", "controls"];
 
@@ -369,6 +375,30 @@ impl KeptReader {
                 Err(why) => cx.warn(format!("links to external workbooks were dropped: {why}")),
             }
         }
+        // Excel trusts the saved cell values only when both are present; without them it
+        // recalculates everything on open, and links into closed workbooks come back as errors.
+        if let Some(v) = wb_xml.child("fileVersion") {
+            let mut x = String::from("<fileVersion");
+            for k in FILE_VERSION_ATTRS {
+                if let Some(a) = v.attr(k) {
+                    let _ = write!(x, " {k}=\"{}\"", esc_attr(a));
+                }
+            }
+            x.push_str("/>");
+            p.elements.push(PreservedXml { slot: "fileVersion".into(), xml: x });
+        }
+        let calc_features = wb_xml
+            .child("extLst")
+            .and_then(|l| l.kids("ext").find(|e| e.attr("uri").is_some_and(|u| u.eq_ignore_ascii_case(CALC_FEATURES_URI))))
+            .and_then(|e| e.child("calcFeatures"));
+        if let Some(c) = calc_features {
+            let mut x = format!("<ext uri=\"{CALC_FEATURES_URI}\" xmlns:xcalcf=\"{NS_CALC_FEATURES}\"><xcalcf:calcFeatures>");
+            for name in c.kids("feature").filter_map(|f| f.attr("name")) {
+                let _ = write!(x, "<xcalcf:feature name=\"{}\"/>", esc_attr(name));
+            }
+            x.push_str("</xcalcf:calcFeatures></ext>");
+            p.elements.push(PreservedXml { slot: "ext".into(), xml: x });
+        }
         (!p.is_empty()).then(|| Arc::new(p))
     }
 
@@ -853,6 +883,12 @@ pub fn write_workbook(wb: &Workbook, wb_rels: &mut Rels, out: &mut Out) -> Strin
     p.elements.iter().filter(|e| e.slot == "externalReferences").filter_map(|e| remap(&e.xml, &ids)).collect()
 }
 
+/// The workbook's kept elements of `slot` that refer to no part (`fileVersion`, `ext`).
+pub fn workbook_elements(wb: &Workbook, slot: &str) -> String {
+    let Some(p) = wb.preserved.as_deref() else { return String::new() };
+    p.elements.iter().filter(|e| e.slot == slot).map(|e| e.xml.as_str()).collect()
+}
+
 /// Adds the kept package-root relationships (custom properties…) to `_rels/.rels`.
 pub fn write_package_rels(root: &mut Rels, out: &mut Out) {
     for (ty, target, external) in std::mem::take(&mut out.kept.root) {
diff --git a/crates/xlsx/src/pivot.rs b/crates/xlsx/src/pivot.rs
index 1d16ab3..609ae53 100644
--- a/crates/xlsx/src/pivot.rs
+++ b/crates/xlsx/src/pivot.rs
@@ -810,6 +810,9 @@ fn table_xml(pt: &PivotTable, idx: usize, cache_id: u32, c: &Cache, fmt_id: &dyn
         PivotLayout::Outline => s.push_str(" compact=\"0\" compactData=\"0\" outline=\"1\" outlineData=\"1\""),
         PivotLayout::Tabular => s.push_str(" compact=\"0\" compactData=\"0\""),
     }
+    if pt.values_on_rows {
+        s.push_str(" dataOnRows=\"1\"");
+    }
     if !pt.show_headers {
         s.push_str(" showHeaders=\"0\"");
     }
@@ -826,13 +829,20 @@ fn table_xml(pt: &PivotTable, idx: usize, cache_id: u32, c: &Cache, fmt_id: &dyn
     let end = pt.last_range.map(|r| r.end).unwrap_or(a);
     let loc = RangeRef::new(a, CellRef::new(end.row.max(a.row), end.col.max(a.col)));
     let k = vals.len();
-    let first_data_row = if col_idx.is_empty() { 1 } else { 1 + col_idx.len() + usize::from(k > 1) };
-    let first_data_col = if row_idx.is_empty() && col_idx.is_empty() {
+    // Σ Values (two or more value fields): its index among the written fields of its axis.
+    let (row_map, _) = c.axis_map.split_at(pt.rows.len().min(c.axis_map.len()));
+    let values_at = |map: &[Option<usize>], n: usize| pt.values_position.map_or(n, |p| map.iter().take(p).filter(|x| x.is_some()).count());
+    let row_values = (k > 1 && pt.values_on_rows).then(|| values_at(row_map, row_idx.len()));
+    // In Columns Σ Values comes after the last field: the column layout doesn't place it elsewhere.
+    let col_values = (k > 1 && !pt.values_on_rows).then_some(col_idx.len());
+    let first_data_row = if col_idx.is_empty() { 1 } else { 1 + col_idx.len() + usize::from(col_values.is_some()) };
+    let row_levels = row_idx.len() + usize::from(row_values.is_some());
+    let first_data_col = if row_levels == 0 && col_idx.is_empty() {
         0
     } else if compact {
         1
     } else {
-        row_idx.len().max(1)
+        row_levels.max(1)
     };
     let _ = write!(s, "<location ref=\"{}\" firstHeaderRow=\"1\" firstDataRow=\"{first_data_row}\" firstDataCol=\"{first_data_col}\"", loc.a1());
     if !pages.is_empty() {
@@ -922,24 +932,8 @@ fn table_xml(pt: &PivotTable, idx: usize, cache_id: u32, c: &Cache, fmt_id: &dyn
     }
     s.push_str("</pivotFields>");
 
-    if !row_idx.is_empty() {
-        let _ = write!(s, "<rowFields count=\"{}\">", row_idx.len());
-        for i in &row_idx {
-            let _ = write!(s, "<field x=\"{i}\"/>");
-        }
-        s.push_str("</rowFields>");
-    }
-    let values_field = k > 1;
-    if !col_idx.is_empty() || values_field {
-        let _ = write!(s, "<colFields count=\"{}\">", col_idx.len() + usize::from(values_field));
-        for i in &col_idx {
-            let _ = write!(s, "<field x=\"{i}\"/>");
-        }
-        if values_field {
-            s.push_str("<field x=\"-2\"/>");
-        }
-        s.push_str("</colFields>");
-    }
+    axis_fields_xml(&mut s, "rowFields", &row_idx, row_values);
+    axis_fields_xml(&mut s, "colFields", &col_idx, col_values);
     if !pages.is_empty() {
         let _ = write!(s, "<pageFields count=\"{}\">", pages.len());
         for (i, f) in &pages {
@@ -1011,6 +1005,25 @@ fn table_xml(pt: &PivotTable, idx: usize, cache_id: u32, c: &Cache, fmt_id: &dyn
     s
 }
 
+/// `<rowFields>`/`<colFields>`: the axis's cache field indices, with Σ Values (`-2`) at `values_at`.
+fn axis_fields_xml(s: &mut String, tag: &str, idx: &[usize], values_at: Option<usize>) {
+    let n = idx.len() + usize::from(values_at.is_some());
+    if n == 0 {
+        return;
+    }
+    let _ = write!(s, "<{tag} count=\"{n}\">");
+    for (j, i) in idx.iter().enumerate() {
+        if values_at == Some(j) {
+            s.push_str("<field x=\"-2\"/>");
+        }
+        let _ = write!(s, "<field x=\"{i}\"/>");
+    }
+    if values_at.is_some_and(|p| p >= idx.len()) {
+        s.push_str("<field x=\"-2\"/>");
+    }
+    let _ = write!(s, "</{tag}>");
+}
+
 // ================================================================ reading
 
 /// A cache field as read.
@@ -1253,18 +1266,21 @@ fn read_table(cx: &mut Ctx<'_>, x: &El, cache: &CacheIn, id: u32) -> Option<Pivo
     pt.grand_totals_cols = x.flag("colGrandTotals", true);
     pt.show_headers = x.flag("showHeaders", true);
     pt.style = x.child("pivotTableStyleInfo").and_then(|s| s.attr("name")).unwrap_or("").to_string();
-    if x.flag("dataOnRows", false) {
-        cx.warn(format!("PivotTable \"{}\": values on rows are shown on columns", pt.name));
-    }
     if x.child("calculatedItems").is_some() || x.path(&["filters", "filter"]).is_some() {
         cx.warn(format!("PivotTable \"{}\": calculated items and label/value filters are not supported", pt.name));
     }
 
     let mut filters: Vec<PivotFilter> = Vec::new();
 
-    let axis = |cx: &mut Ctx<'_>, list: &[i64], filters: &mut Vec<PivotFilter>| -> Vec<PivotField> {
+    // (fields, position of Σ Values (`-2`) among them)
+    let axis = |cx: &mut Ctx<'_>, list: &[i64], filters: &mut Vec<PivotFilter>| -> (Vec<PivotField>, Option<usize>) {
         let mut v = Vec::new();
+        let mut values_at = None;
         for &i in list {
+            if i == -2 {
+                values_at = Some(v.len());
+                continue;
+            }
             if i < 0 {
                 continue;
             }
@@ -1290,7 +1306,7 @@ fn read_table(cx: &mut Ctx<'_>, x: &El, cache: &CacheIn, id: u32) -> Option<Pivo
             }
             v.push(f);
         }
-        v
+        (v, values_at)
     };
     let mut page_filters = Vec::new();
     for p in &pages {
@@ -1314,8 +1330,15 @@ fn read_table(cx: &mut Ctx<'_>, x: &El, cache: &CacheIn, id: u32) -> Option<Pivo
         page_filters.push(PivotFilter { source_col: name, selected });
     }
     let mut axis_filters = Vec::new();
-    pt.rows = axis(cx, &row_x, &mut axis_filters);
-    pt.columns = axis(cx, &col_x, &mut axis_filters);
+    let (rows, rows_values) = axis(cx, &row_x, &mut axis_filters);
+    let (columns, cols_values) = axis(cx, &col_x, &mut axis_filters);
+    pt.rows = rows;
+    pt.columns = columns;
+    // Σ Values: where its `-2` entry is, else `dataOnRows` and `dataPosition`; after the last
+    // field by default. In Columns it always comes last, as the column layout puts it there.
+    pt.values_on_rows = rows_values.is_some() || (cols_values.is_none() && x.flag("dataOnRows", false));
+    pt.values_position =
+        if pt.values_on_rows { rows_values.or_else(|| x.attr_u32("dataPosition").map(|p| p as usize)).filter(|p| *p < pt.rows.len()) } else { None };
     filters.extend(page_filters);
     filters.extend(axis_filters);
     pt.filters = filters;
diff --git a/crates/xlsx/src/read.rs b/crates/xlsx/src/read.rs
index a25444d..ed7996a 100644
--- a/crates/xlsx/src/read.rs
+++ b/crates/xlsx/src/read.rs
@@ -28,6 +28,8 @@ pub struct Ctx<'a> {
     pub num_fmts: std::collections::HashMap<u32, String>,
     /// Value metadata blocks, indexed by the worksheet's one-based `vm` attribute.
     pub cell_pictures: Vec<Option<Arc<CellPicture>>>,
+    /// x14 conditional-format ids of the current sheet's data bars, with the index of the rule in `cond_formats`.
+    pub cf_ext_ids: Vec<(String, usize)>,
 }
 
 impl Ctx<'_> {
@@ -79,6 +81,7 @@ pub fn read_xlsx(bytes: &[u8]) -> Result<(Workbook, ReadReport), IoError> {
         next_id: 1,
         num_fmts: Default::default(),
         cell_pictures: vec![],
+        cf_ext_ids: vec![],
     };
     let root_rels = cx.pkg.rels("")?;
     let wb_part = find_rel(&root_rels, "officeDocument").map(|r| r.target.clone()).unwrap_or_else(|| "xl/workbook.xml".into());
@@ -120,6 +123,10 @@ pub fn read_xlsx(bytes: &[u8]) -> Result<(Workbook, ReadReport), IoError> {
         if let Some(x) = cx.optional_xml(&r.target)? {
             let StylesIn { xfs, dxfs, palette, named, num_fmts } = read_styles(&x, &checkboxes);
             cx.num_fmts = num_fmts;
+            // Cell format 0 is the Normal style: its font is what every unformatted cell shows.
+            if let Some(normal) = xfs.first() {
+                cx.styles = StyleTable::with_default(Style { font: normal.font.clone(), ..Style::default() });
+            }
             cx.xf_map = xfs.into_iter().enumerate().map(|(i, s)| if i == 0 { StyleId::DEFAULT } else { cx.styles.intern(s) }).collect();
             cx.dxfs = dxfs;
             cx.palette = palette;
@@ -301,7 +308,7 @@ pub fn read_xlsx(bytes: &[u8]) -> Result<(Workbook, ReadReport), IoError> {
     if let Some(r) = find_rel(&root_rels, "core-properties").cloned()
         && let Ok(Some(x)) = cx.pkg.read_xml(&r.target)
     {
-        let get = |n: &str| x.child(n).map(|e| e.text.trim().to_string()).unwrap_or_default();
+        let get = |n: &str| x.child(n).map(|e| e.text.clone()).unwrap_or_default();
         wb.props.title = get("title");
         wb.props.subject = get("subject");
         wb.props.author = get("creator");
@@ -311,7 +318,7 @@ pub fn read_xlsx(bytes: &[u8]) -> Result<(Workbook, ReadReport), IoError> {
     if let Some(r) = find_rel(&root_rels, "extended-properties").cloned()
         && let Ok(Some(x)) = cx.pkg.read_xml(&r.target)
     {
-        wb.props.company = x.child("Company").map(|e| e.text.trim().to_string()).unwrap_or_default();
+        wb.props.company = x.child("Company").map(|e| e.text.clone()).unwrap_or_default();
     }
 
     // A VBA project is carried through unchanged: GridCraft never runs macros, but preserving the
diff --git a/crates/xlsx/src/sheet_read.rs b/crates/xlsx/src/sheet_read.rs
index 77b46d9..61857a7 100644
--- a/crates/xlsx/src/sheet_read.rs
+++ b/crates/xlsx/src/sheet_read.rs
@@ -60,6 +60,7 @@ pub fn read_sheet(cx: &mut Ctx<'_>, part: &str, name: &str) -> Result<Sheet, IoE
     drop(bytes);
 
     let mut fit_to_page = false;
+    cx.cf_ext_ids.clear();
     for e in &root.children {
         match e.name.as_str() {
             "sheetPr" => {
@@ -104,7 +105,7 @@ pub fn read_sheet(cx: &mut Ctx<'_>, part: &str, name: &str) -> Result<Sheet, IoE
                     }
                 }
             }
-            "hyperlinks" => read_hyperlinks(e, &rels, &mut sheet),
+            "hyperlinks" => read_hyperlinks(cx, name, e, &rels, &mut sheet),
             "autoFilter" => sheet.autofilter = read_autofilter(cx, e),
             "printOptions" => {
                 sheet.print.gridlines = e.flag("gridLines", false);
@@ -541,7 +542,7 @@ pub fn parse_iso_datetime(s: &str, sys: DateSystem) -> Option<f64> {
 }
 
 pub fn parse_sqref(s: Option<&str>) -> Vec<RangeRef> {
-    s.unwrap_or("").split_whitespace().filter_map(RangeRef::parse).take(10_000).collect()
+    s.unwrap_or("").split_whitespace().filter_map(RangeRef::parse).collect()
 }
 
 fn cf_op(s: Option<&str>) -> CfOperator {
@@ -596,6 +597,12 @@ fn read_cf(cx: &mut Ctx<'_>, e: &El, sheet: &mut Sheet) {
         let formulas: Vec<String> = r.kids("formula").map(|f| from_file(f.text.trim())).collect();
         let f0 = formulas.first().cloned().unwrap_or_default();
         let text = r.attr("text").unwrap_or("").to_string();
+        // The x14 id that links a data bar to its Excel 2010 extension (solid fill lives there).
+        let ext_id = r
+            .child("extLst")
+            .and_then(|l| l.kids("ext").find_map(|x| x.child("id")))
+            .map(|i| i.text.trim().to_string())
+            .filter(|i| !i.is_empty());
         let rule = match r.attr("type").unwrap_or("") {
             "cellIs" => CfRule::CellIs { op: cf_op(r.attr("operator")), a: f0, b: formulas.get(1).cloned(), style },
             "expression" => CfRule::Expression { formula: f0, style },
@@ -649,6 +656,9 @@ fn read_cf(cx: &mut Ctx<'_>, e: &El, sheet: &mut Sheet) {
                 continue;
             }
         };
+        if let Some(id) = ext_id {
+            cx.cf_ext_ids.push((id, sheet.cond_formats.len()));
+        }
         sheet.cond_formats.push(CondFormat {
             ranges: ranges.clone(),
             rule,
@@ -709,11 +719,13 @@ fn read_validation(v: &El) -> Option<Validation> {
     })
 }
 
-fn read_hyperlinks(e: &El, rels: &[Rel], sheet: &mut Sheet) {
+fn read_hyperlinks(cx: &mut Ctx<'_>, name: &str, e: &El, rels: &[Rel], sheet: &mut Sheet) {
     let mut cells = 0u64;
     for h in e.kids("hyperlink") {
         let Some(range) = h.attr("ref").and_then(RangeRef::parse) else { continue };
         let mut target = h.attr("id").and_then(|id| rels.iter().find(|r| r.id == id)).map(|r| r.target.clone()).unwrap_or_default();
+        // A relationship is a file or web page; a bare `location` is a place in this workbook.
+        let external = !target.is_empty();
         if let Some(loc) = h.attr("location").filter(|l| !l.is_empty()) {
             if target.is_empty() {
                 target = loc.trim_start_matches('#').to_string();
@@ -724,9 +736,10 @@ fn read_hyperlinks(e: &El, rels: &[Rel], sheet: &mut Sheet) {
         if target.is_empty() {
             continue;
         }
-        let link = Hyperlink { target, tooltip: h.attr("tooltip").map(str::to_string) };
+        let link = Hyperlink { target, tooltip: h.attr("tooltip").map(str::to_string), external };
         for c in range.iter() {
             if cells >= MAX_HYPERLINK_CELLS {
+                cx.warn(format!("sheet \"{name}\": hyperlinks past the first {MAX_HYPERLINK_CELLS} cells were dropped"));
                 return;
             }
             cells += 1;
@@ -953,7 +966,23 @@ fn read_ext(cx: &mut Ctx<'_>, e: &El, sheet: &mut Sheet) {
                         }
                     }
                 }
-                "conditionalFormattings" => cx.warn("some Excel 2010 conditional format extensions were skipped"),
+                "conditionalFormattings" => {
+                    let mut skipped = false;
+                    for r in c.kids("conditionalFormatting").flat_map(|f| f.kids("cfRule")) {
+                        let idx = r.attr("id").and_then(|id| cx.cf_ext_ids.iter().find(|(i, _)| i == id)).map(|(_, n)| *n);
+                        match (idx.and_then(|n| sheet.cond_formats.get_mut(n)), r.child("dataBar")) {
+                            (Some(CondFormat { rule: CfRule::DataBar { gradient, .. }, .. }), Some(db)) => {
+                                *gradient = db.flag("gradient", true);
+                                // Only the fill style is modelled; borders, lengths, axis or negative colours are lost.
+                                skipped |= db.attrs.iter().any(|(k, _)| k != "gradient") || db.children.iter().any(|k| k.name != "cfvo");
+                            }
+                            _ => skipped = true,
+                        }
+                    }
+                    if skipped {
+                        cx.warn("some Excel 2010 conditional format extensions were skipped");
+                    }
+                }
                 _ => {}
             }
         }
@@ -973,4 +1002,12 @@ mod tests {
         assert_eq!(parse_iso_datetime("garbage", DateSystem::D1900), None);
         assert_eq!(parse_iso_datetime("2024-13-01", DateSystem::D1900), None);
     }
+
+    #[test]
+    fn sqref_keeps_more_than_ten_thousand_ranges() {
+        let sq = (1..=12_000).map(|r| format!("A{r}")).collect::<Vec<_>>().join(" ");
+        let ranges = parse_sqref(Some(&sq));
+        assert_eq!(ranges.len(), 12_000);
+        assert_eq!(ranges.last().copied(), RangeRef::parse("A12000"));
+    }
 }
diff --git a/crates/xlsx/src/sheet_write.rs b/crates/xlsx/src/sheet_write.rs
index 0bfcb7d..4196155 100644
--- a/crates/xlsx/src/sheet_write.rs
+++ b/crates/xlsx/src/sheet_write.rs
@@ -81,7 +81,7 @@ pub fn write_sheet(wb: &Workbook, si: usize, selected: bool, out: &mut Out) -> (
     let tables: Vec<(&Table, Vec<String>)> = sheet
         .tables
         .iter()
-        .filter(|t| t.range.height() > t.header_row as u32 + t.totals_row as u32 || (t.header_row && !t.totals_row && t.range.height() >= 1))
+        .filter(|t| t.range.height() > t.header_row as u32 + t.totals_row as u32 || (t.header_row && t.range.height() > t.totals_row as u32))
         .map(|t| (t, table_columns(t)))
         .collect();
     for (t, cols) in &tables {
@@ -388,7 +388,10 @@ pub fn write_sheet(wb: &Workbook, si: usize, selected: bool, out: &mut Out) -> (
             if t.is_empty() {
                 continue;
             }
-            let external = t.contains("://")
+            // `external` is what the file said, or what Insert › Link chose; the scheme test covers
+            // links made before the flag existed.
+            let external = h.external
+                || t.contains("://")
                 || t.to_ascii_lowercase().starts_with("mailto:")
                 || t.starts_with("\\\\")
                 || t.to_ascii_lowercase().starts_with("file:");
@@ -573,9 +576,33 @@ pub fn write_sheet(wb: &Workbook, si: usize, selected: bool, out: &mut Out) -> (
         }
         let _ = write!(s, "<tableParts count=\"{}\">{parts}</tableParts>", tables.len());
     }
-    // Sparklines (Excel 2010 extension).
+    // Excel 2010 extensions: solid data bars, then sparklines.
+    let solid_bars: Vec<(&CondFormat, u32)> = sheet
+        .cond_formats
+        .iter()
+        .enumerate()
+        .filter(|(_, cf)| !cf.ranges.is_empty() && matches!(cf.rule, CfRule::DataBar { gradient: false, .. }))
+        .map(|(i, cf)| (cf, prio.get(i).copied().unwrap_or(1)))
+        .collect();
+    if !solid_bars.is_empty() || !sheet.sparklines.is_empty() {
+        s.push_str("<extLst>");
+    }
+    if !solid_bars.is_empty() {
+        let _ = write!(
+            s,
+            "<ext uri=\"{{78C0D931-6437-407d-A8A1-0F90B4350D7D}}\" xmlns:x14=\"{X14_NS}\" xmlns:xm=\"{XM_NS}\"><x14:conditionalFormattings>"
+        );
+        for (cf, p) in &solid_bars {
+            if let CfRule::DataBar { min, max, .. } = &cf.rule {
+                let (id, lo, hi) = (solid_bar_id(*p), x14_cfvo(min), x14_cfvo(max));
+                let _ = write!(s, "<x14:conditionalFormatting><x14:cfRule type=\"dataBar\" id=\"{id}\"><x14:dataBar gradient=\"0\">{lo}{hi}");
+                let _ = write!(s, "</x14:dataBar></x14:cfRule><xm:sqref>{}</xm:sqref></x14:conditionalFormatting>", sqref(&cf.ranges));
+            }
+        }
+        s.push_str("</x14:conditionalFormattings></ext>");
+    }
     if !sheet.sparklines.is_empty() {
-        s.push_str("<extLst><ext uri=\"{05C60535-1F16-4fd2-B633-F4F36F0B64E0}\" xmlns:x14=\"http://schemas.microsoft.com/office/spreadsheetml/2009/9/main\"><x14:sparklineGroups xmlns:xm=\"http://schemas.microsoft.com/office/excel/2006/main\">");
+        let _ = write!(s, "<ext uri=\"{{05C60535-1F16-4fd2-B633-F4F36F0B64E0}}\" xmlns:x14=\"{X14_NS}\"><x14:sparklineGroups xmlns:xm=\"{XM_NS}\">");
         for sp in &sheet.sparklines {
             let ty = match sp.kind {
                 SparklineKind::Line => "",
@@ -593,7 +620,10 @@ pub fn write_sheet(wb: &Workbook, si: usize, selected: bool, out: &mut Out) -> (
                 sp.cell.a1()
             );
         }
-        s.push_str("</x14:sparklineGroups></ext></extLst>");
+        s.push_str("</x14:sparklineGroups></ext>");
+    }
+    if !solid_bars.is_empty() || !sheet.sparklines.is_empty() {
+        s.push_str("</extLst>");
     }
     s.push_str("</worksheet>");
     (s, rels)
@@ -714,6 +744,33 @@ fn quote(t: &str) -> String {
     format!("\"{}\"", t.replace('"', "\"\""))
 }
 
+const X14_NS: &str = "http://schemas.microsoft.com/office/spreadsheetml/2009/9/main";
+const XM_NS: &str = "http://schemas.microsoft.com/office/excel/2006/main";
+
+/// The id linking a solid data bar's `cfRule` to its x14 extension; unique per sheet because priorities are.
+fn solid_bar_id(priority: u32) -> String {
+    format!("{{00000000-0000-0000-0000-{priority:012}}}")
+}
+
+/// The `cfRule` extension that points a solid data bar at its x14 rule.
+fn solid_bar_ext(priority: u32) -> String {
+    let id = solid_bar_id(priority);
+    format!("<extLst><ext uri=\"{{B025F937-C7B1-47D3-B67F-A62EFF666E3E}}\" xmlns:x14=\"{X14_NS}\"><x14:id>{id}</x14:id></ext></extLst>")
+}
+
+/// An x14 `cfvo`: unlike the 2006 one it has no `val` attribute, the value is an `xm:f` child.
+fn x14_cfvo(v: &CfValueKind) -> String {
+    let (ty, val) = match v {
+        CfValueKind::Min => return "<x14:cfvo type=\"min\"/>".into(),
+        CfValueKind::Max => return "<x14:cfvo type=\"max\"/>".into(),
+        CfValueKind::Number(n) => ("num", num(*n)),
+        CfValueKind::Percent(n) => ("percent", num(*n)),
+        CfValueKind::Percentile(n) => ("percentile", num(*n)),
+        CfValueKind::Formula(f) => ("formula", text_to_file(f)),
+    };
+    format!("<x14:cfvo type=\"{ty}\"><xm:f>{}</xm:f></x14:cfvo>", esc(&val))
+}
+
 fn cf_rule_xml(cf: &CondFormat, priority: u32, out: &mut Out) -> String {
     let tl = cf.ranges.first().map(|r| r.start.a1()).unwrap_or_else(|| "A1".into());
     let stop = if cf.stop_if_true { " stopIfTrue=\"1\"" } else { "" };
@@ -809,12 +866,13 @@ fn cf_rule_xml(cf: &CondFormat, priority: u32, out: &mut Out) -> String {
             b.push_str("</colorScale>");
             format!("<cfRule type=\"colorScale\" priority=\"{priority}\"{stop}>{b}</cfRule>")
         }
-        CfRule::DataBar { min, max, color, show_value, .. } => format!(
-            "<cfRule type=\"dataBar\" priority=\"{priority}\"{stop}><dataBar{}>{}{}<color {}/></dataBar></cfRule>",
+        CfRule::DataBar { min, max, color, show_value, gradient } => format!(
+            "<cfRule type=\"dataBar\" priority=\"{priority}\"{stop}><dataBar{}>{}{}<color {}/></dataBar>{}</cfRule>",
             if *show_value { "" } else { " showValue=\"0\"" },
             cfvo_xml(min),
             cfvo_xml(max),
-            if *color == Color::Auto { "rgb=\"FF638EC6\"".to_string() } else { color_attrs(color) }
+            if *color == Color::Auto { "rgb=\"FF638EC6\"".to_string() } else { color_attrs(color) },
+            if *gradient { String::new() } else { solid_bar_ext(priority) }
         ),
         CfRule::IconSet { set, thresholds, reverse, show_value } => {
             let mut b = format!("<iconSet iconSet=\"{}\"", esc_attr(set));
diff --git a/crates/xlsx/src/styles.rs b/crates/xlsx/src/styles.rs
index 1c98a54..01f1fa6 100644
--- a/crates/xlsx/src/styles.rs
+++ b/crates/xlsx/src/styles.rs
@@ -396,7 +396,8 @@ pub fn color_attrs(c: &Color) -> String {
     }
 }
 
-fn font_xml(f: &Font, dxf: bool) -> String {
+/// `minor`: the font follows the theme's body font (`<scheme val="minor"/>`).
+fn font_xml(f: &Font, dxf: bool, minor: bool) -> String {
     let mut s = String::from("<font>");
     if f.bold {
         s.push_str("<b/>");
@@ -429,6 +430,9 @@ fn font_xml(f: &Font, dxf: bool) -> String {
     }
     if !dxf {
         let _ = write!(s, "<name val=\"{}\"/><family val=\"2\"/>", esc_attr(&f.name));
+        if minor {
+            s.push_str("<scheme val=\"minor\"/>");
+        }
     }
     s.push_str("</font>");
     s
@@ -667,7 +671,7 @@ pub fn write_styles(wb: &Workbook, dxfs: &[Style], extra_fmts: &[String]) -> (St
             || d.font.color != Color::Auto
             || d.font.vert != VertAlign::Baseline
         {
-            dx.push_str(&font_xml(&d.font, true));
+            dx.push_str(&font_xml(&d.font, true, false));
         }
         if d.num_fmt != def.num_fmt {
             let id = nf.id(d.num_fmt.as_str());
@@ -699,8 +703,9 @@ pub fn write_styles(wb: &Workbook, dxfs: &[Style], extra_fmts: &[String]) -> (St
         s.push_str("</numFmts>");
     }
     let _ = write!(s, "<fonts count=\"{}\">", fonts.len());
-    for f in &fonts {
-        s.push_str(&font_xml(f, false));
+    for (i, f) in fonts.iter().enumerate() {
+        // A Normal font in the theme's body face follows the theme, as Excel writes it (#805).
+        s.push_str(&font_xml(f, false, i == 0 && f.name == wb.theme.minor_font));
     }
     let _ = write!(s, "</fonts><fills count=\"{}\">", fills.len());
     for f in &fills {
diff --git a/crates/xlsx/src/tests/array_export.rs b/crates/xlsx/src/tests/array_export.rs
index 0491efd..45764e4 100644
--- a/crates/xlsx/src/tests/array_export.rs
+++ b/crates/xlsx/src/tests/array_export.rs
@@ -200,6 +200,43 @@ fn calculated_table_column_keeps_formula_and_cell_value() {
     assert_eq!(sh.value(at("B2")), Value::Number(6.0));
 }
 
+#[test]
+fn this_row_references_are_written_in_long_form() {
+    let mut wb = Workbook::new();
+    let sh = wb.sheet_mut(0).unwrap();
+    sh.cells.set(at("A2"), Cell::value(Value::Number(3.0)));
+    sh.cells.set(at("B2"), formula("Data[@Input]*2", 6.0));
+    sh.tables.push(Table {
+        id: 1,
+        name: "Data".into(),
+        range: range("A1:B2"),
+        header_row: true,
+        totals_row: false,
+        columns: vec![
+            TableColumn { name: "Input".into(), totals: TotalsFn::None, totals_label: None, formula: None },
+            TableColumn { name: "Output".into(), totals: TotalsFn::None, totals_label: None, formula: Some("[@Input]*2".into()) },
+        ],
+        style: "TableStyleLight1".into(),
+        banded_rows: true,
+        banded_cols: false,
+        first_col: false,
+        last_col: false,
+        filter_button: true,
+        filter: vec![],
+    });
+    let bytes = write_xlsx(&wb).unwrap();
+    let mut pkg = Package::open(&bytes).unwrap();
+    let sheet = pkg.read_xml("xl/worksheets/sheet1.xml").unwrap().unwrap();
+    assert_eq!(cell(&sheet, "B2").child("f").unwrap().text, "Data[[#This Row],[Input]]*2");
+    let table = pkg.read_xml("xl/tables/table1.xml").unwrap().unwrap();
+    let column = table.child("tableColumns").unwrap().kids("tableColumn").nth(1).unwrap();
+    assert_eq!(column.child("calculatedColumnFormula").unwrap().text, "[[#This Row],[Input]]*2");
+    let (back, _) = read_xlsx(&bytes).unwrap();
+    let sh = back.sheet(0).unwrap();
+    assert_eq!(sh.tables[0].columns[1].formula.as_deref(), Some("[@Input]*2"));
+    assert_eq!(sh.cell(at("B2")).unwrap().formula.as_ref().unwrap().text, "Data[@Input]*2");
+}
+
 /// Compare both cell and formula metadata, collecting all boundaries in the group on failure.
 fn check_formula_metadata(mut wb: Workbook, sheet_index: usize, cases: &[(&str, bool)]) {
     for (i, (text, _)) in cases.iter().enumerate() {
diff --git a/crates/xlsx/src/tests/chart_bool_default.rs b/crates/xlsx/src/tests/chart_bool_default.rs
new file mode 100644
index 0000000..e9a074c
--- /dev/null
+++ b/crates/xlsx/src/tests/chart_bool_default.rs
@@ -0,0 +1,32 @@
+//! A `CT_Boolean` chart flag with no `val` attribute is on (ECMA-376), for series smoothing and value labels.
+
+use crate::chart::read_chart;
+use crate::xml::parse;
+
+/// Reads a line chart with `ser` appended to its one series and `group` inside the group's `<c:dLbls>`.
+fn flags(ser: &str, group: &str) -> (bool, bool) {
+    let xml = format!(
+        "<c:chartSpace xmlns:c=\"http://schemas.openxmlformats.org/drawingml/2006/chart\"><c:chart><c:plotArea><c:lineChart>\
+         <c:grouping val=\"standard\"/><c:ser><c:idx val=\"0\"/><c:order val=\"0\"/>\
+         <c:val><c:numRef><c:f>Data!$A$1:$A$5</c:f></c:numRef></c:val>{ser}</c:ser><c:dLbls>{group}</c:dLbls>\
+         <c:axId val=\"1\"/><c:axId val=\"2\"/></c:lineChart><c:catAx><c:axId val=\"1\"/></c:catAx><c:valAx><c:axId val=\"2\"/></c:valAx>\
+         </c:plotArea></c:chart></c:chartSpace>"
+    );
+    let root = parse(xml.as_bytes()).unwrap();
+    let ch = read_chart(&root).unwrap();
+    (ch.series[0].smooth, ch.data_labels)
+}
+
+#[test]
+fn omitted_val_means_on() {
+    assert_eq!(flags("<c:smooth/>", "<c:showVal/>"), (true, true));
+    assert_eq!(flags("<c:dLbls><c:showVal/></c:dLbls>", ""), (false, true), "series-level value labels");
+}
+
+#[test]
+fn explicit_values_are_honoured() {
+    assert_eq!(flags("<c:smooth val=\"1\"/>", "<c:showVal val=\"1\"/>"), (true, true));
+    assert_eq!(flags("<c:smooth val=\"true\"/>", "<c:showVal val=\"true\"/>"), (true, true));
+    assert_eq!(flags("<c:smooth val=\"0\"/>", "<c:showVal val=\"0\"/>"), (false, false));
+    assert_eq!(flags("", ""), (false, false));
+}
diff --git a/crates/xlsx/src/tests/fixtures.rs b/crates/xlsx/src/tests/fixtures.rs
index 47dde5a..39ea309 100644
--- a/crates/xlsx/src/tests/fixtures.rs
+++ b/crates/xlsx/src/tests/fixtures.rs
@@ -278,6 +278,63 @@ Check this</t></r></text></comment></commentList></comments>"#;
     assert_eq!(s.sparklines[0].kind, gridcraft_model::SparklineKind::Column);
 }
 
+/// The sheet's hyperlinks as written: cell, relationship target (external only), location.
+fn written_links(bytes: &[u8]) -> Vec<(String, Option<String>, Option<String>)> {
+    let mut pkg = crate::package::Package::open(bytes).unwrap();
+    let rels = pkg.rels("xl/worksheets/sheet1.xml").unwrap();
+    let sheet = pkg.read_xml("xl/worksheets/sheet1.xml").unwrap().unwrap();
+    let Some(links) = sheet.child("hyperlinks") else { return vec![] };
+    links
+        .kids("hyperlink")
+        .map(|h| {
+            let rel = h.attr("id").map(|id| rels.iter().find(|r| r.id == id).unwrap());
+            let target = rel.map(|r| {
+                assert!(r.external && r.kind == "hyperlink", "{r:?}");
+                r.target.clone()
+            });
+            (h.attr("ref").unwrap().to_string(), target, h.attr("location").map(str::to_string))
+        })
+        .collect()
+}
+
+/// A link to another file is a relationship (`TargetMode="External"`) in the file, with the place in
+/// it as `location`. Saved as a bare `location`, Excel takes it for a place in this workbook and the
+/// link no longer opens the file (#800). C16 is Apache POI's `WithMoreVariousData.xlsx`.
+#[test]
+fn hyperlink_to_another_file_stays_external() {
+    let body = r#"<sheetData/><hyperlinks><hyperlink ref="C16" r:id="rId2"/><hyperlink ref="C17" r:id="rId3" location="Sheet1!A2"/>
+      <hyperlink ref="C18" r:id="rId4"/><hyperlink ref="C19" location="Data!B2"/><hyperlink ref="C20" r:id="rId5"/></hyperlinks>"#;
+    let rel = |id: &str, target: &str| {
+        format!(
+            r#"<Relationship Id="{id}" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink" Target="{target}" TargetMode="External"/>"#
+        )
+    };
+    let sheet_rels = format!(
+        r#"<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">{}{}{}{}</Relationships>"#,
+        rel("rId2", "WithVariousData.xlsx"),
+        rel("rId3", "Source.xlsx"),
+        rel("rId4", r"..\Reports\Q1.xlsx"),
+        rel("rId5", "https://example.com/a.xlsx"),
+    );
+    let bytes = minimal(body, &[("xl/worksheets/_rels/sheet1.xml.rels", &sheet_rels)], "", "");
+    let (wb, _) = read_xlsx(&bytes).unwrap();
+    let s = wb.sheet(0).unwrap();
+    assert!(s.hyperlinks[&at("C16")].external && !s.hyperlinks[&at("C19")].external);
+
+    let some = |s: &str| Some(s.to_string());
+    let links = written_links(&crate::write_xlsx(&wb).unwrap());
+    assert_eq!(
+        links,
+        vec![
+            ("C16".into(), some("WithVariousData.xlsx"), None),
+            ("C17".into(), some("Source.xlsx"), some("Sheet1!A2")),
+            ("C18".into(), some(r"..\Reports\Q1.xlsx"), None),
+            ("C19".into(), None, some("Data!B2")),
+            ("C20".into(), some("https://example.com/a.xlsx"), None),
+        ]
+    );
+}
+
 #[test]
 fn drawing_with_picture_and_chart() {
     let png: &[u8] = b"\x89PNG\r\n\x1a\nfakeimagedata";
@@ -495,3 +552,28 @@ fn text_box_formatting_is_read_and_written() {
     assert_eq!(rgb(g.text_outline.map(|o| o.0)), rgb(f.text_outline.map(|o| o.0)));
     assert_eq!(g.text_outline.map(|o| o.1), Some(1.5));
 }
+
+/// `_xludf.` marks a user-defined call even when a built-in has the same name; dropping it turns
+/// the call into the built-in, and `_xludf.EOMONTH()` into a call Excel repairs away (#726).
+#[test]
+fn user_defined_function_prefix_round_trips() {
+    let cases =
+        [("A1", "_xludf.EOMONTH()"), ("A2", "_xludf.CONCAT(\"a\",\"b\")"), ("A3", "_xludf.SUM(1,2)"), ("A4", "MYUDF(1)"), ("A5", "_xludf.MYUDF(1)")];
+    let rows: String = cases
+        .iter()
+        .enumerate()
+        .map(|(i, (a, f))| format!(r#"<row r="{}"><c r="{a}"><f>{}</f></c></row>"#, i + 1, f.replace('"', "&quot;")))
+        .collect();
+    let (wb, _) = read_xlsx(&minimal(&format!("<sheetData>{rows}</sheetData>"), &[], "", "")).unwrap();
+    let s = wb.sheet(0).unwrap();
+    for (a, f) in cases {
+        assert_eq!(s.cell(at(a)).unwrap().formula.as_ref().unwrap().text, f, "read {a}");
+    }
+    let bytes = crate::write_xlsx(&wb).unwrap();
+    let mut pkg = crate::package::Package::open(&bytes).unwrap();
+    let sheet = pkg.read_xml("xl/worksheets/sheet1.xml").unwrap().unwrap();
+    for (a, f) in cases {
+        let cell = sheet.child("sheetData").unwrap().kids("row").flat_map(|r| r.kids("c")).find(|c| c.attr("r") == Some(a)).unwrap();
+        assert_eq!(cell.child("f").unwrap().text, f, "written {a}");
+    }
+}
diff --git a/crates/xlsx/src/tests/ink_roundtrip.rs b/crates/xlsx/src/tests/ink_roundtrip.rs
new file mode 100644
index 0000000..2882765
--- /dev/null
+++ b/crates/xlsx/src/tests/ink_roundtrip.rs
@@ -0,0 +1,194 @@
+//! Ink uses visible DrawingML geometry, and only representable polylines become editable ink.
+
+use std::io::Read;
+use std::sync::Arc;
+
+use gridcraft_model::{Anchor, AnchorMode, Color, Shape, ShapeKind, Sheet, Workbook};
+
+use super::minimal;
+use crate::xml::{self, El};
+use crate::{read_xlsx, write_xlsx};
+
+const POINTS: &str = r#"<a:moveTo><a:pt x="-20" y="10"/></a:moveTo><a:lnTo><a:pt x="100" y="80"/></a:lnTo><a:lnTo><a:pt x="180" y="20"/></a:lnTo>"#;
+const PATH: &str = r#"<a:path w="200" h="100" fill="none">"#;
+
+fn drawing() -> String {
+    format!(
+        r#"<xdr:wsDr xmlns:xdr="http://schemas.openxmlformats.org/drawingml/2006/spreadsheetDrawing" xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main">
+        <xdr:oneCellAnchor><xdr:from><xdr:col>0</xdr:col><xdr:colOff>190500</xdr:colOff><xdr:row>0</xdr:row><xdr:rowOff>285750</xdr:rowOff></xdr:from><xdr:ext cx="952500" cy="476250"/>
+        <xdr:sp><xdr:nvSpPr><xdr:cNvPr id="1" name="Independent polyline"/><xdr:cNvSpPr/></xdr:nvSpPr><xdr:spPr>
+        <a:xfrm><a:off x="0" y="0"/><a:ext cx="952500" cy="476250"/></a:xfrm>
+        <a:custGeom><a:avLst/><a:gdLst/><a:ahLst/><a:cxnLst/><a:rect l="0" t="0" r="r" b="b"/><a:pathLst>{PATH}{POINTS}</a:path></a:pathLst></a:custGeom>
+        <a:noFill/><a:ln w="28575" cap="flat"><a:solidFill><a:srgbClr val="A12BCD"/></a:solidFill><a:miter/></a:ln>
+        </xdr:spPr></xdr:sp><xdr:clientData/></xdr:oneCellAnchor></xdr:wsDr>"#
+    )
+}
+
+fn read_drawing(drawing: &str) -> Workbook {
+    let rels = r#"<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships"><Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/drawing" Target="../drawings/drawing1.xml"/></Relationships>"#;
+    let bytes = minimal(
+        r#"<sheetData/><drawing r:id="rId1"/>"#,
+        &[("xl/worksheets/_rels/sheet1.xml.rels", rels), ("xl/drawings/drawing1.xml", drawing)],
+        "",
+        "",
+    );
+    read_xlsx(&bytes).unwrap().0
+}
+
+fn points(shape: &Shape) -> Vec<[f64; 2]> {
+    shape
+        .text
+        .split(';')
+        .map(|pair| {
+            let (x, y) = pair.split_once(',').unwrap();
+            [x.parse().unwrap(), y.parse().unwrap()]
+        })
+        .collect()
+}
+
+fn has_caption(element: &El) -> bool {
+    (element.name == "t" && !element.text.is_empty()) || element.children.iter().any(has_caption)
+}
+
+#[test]
+fn exported_ink_has_a_visible_unfilled_path_and_correct_stroke() {
+    let mut sheet = Sheet::new("Ink");
+    for (id, width) in [(1, 3), (2, 12)] {
+        sheet.shapes.push(Shape {
+            id,
+            kind: ShapeKind::Ink,
+            anchor: Anchor { width: 100.0, height: 50.0, mode: AnchorMode::Absolute, ..Default::default() },
+            fill: Color::Rgb(width << 16),
+            line: Color::Rgb(0xA12BCD),
+            text: "-10.0,5.0;50.0,40.0;90.0,10.0".into(),
+            format: Default::default(),
+        });
+    }
+    let wb = Workbook { sheets: vec![Arc::new(sheet)], ..Default::default() };
+    let bytes = write_xlsx(&wb).unwrap();
+    let mut archive = zip::ZipArchive::new(std::io::Cursor::new(bytes)).unwrap();
+    let mut drawing = String::new();
+    archive.by_name("xl/drawings/drawing1.xml").unwrap().read_to_string(&mut drawing).unwrap();
+    let root = xml::parse(drawing.as_bytes()).unwrap();
+    let shapes: Vec<_> = root.children.iter().filter_map(|anchor| anchor.child("sp")).collect();
+    assert_eq!(shapes.len(), 2);
+    for (shape, width) in shapes.iter().zip([3, 12]) {
+        assert!(!has_caption(shape), "stroke coordinates must not be visible text");
+        let properties = shape.child("spPr").unwrap();
+        assert!(properties.child("prstGeom").is_none());
+        assert!(properties.child("noFill").is_some());
+        let paths: Vec<_> = properties.path(&["custGeom", "pathLst"]).unwrap().kids("path").collect();
+        assert_eq!(paths.len(), 1);
+        let path = paths[0];
+        assert_eq!(path.attr("fill"), Some("none"));
+        let w = path.attr_i64("w").unwrap();
+        let h = path.attr_i64("h").unwrap();
+        assert!(w > 0 && h > 0);
+        assert_eq!(path.children.iter().map(|c| c.name.as_str()).collect::<Vec<_>>(), ["moveTo", "lnTo", "lnTo"]);
+        for (command, [x, y]) in path.children.iter().zip([[-10.0, 5.0], [50.0, 40.0], [90.0, 10.0]]) {
+            let point = command.child("pt").unwrap();
+            let actual_x = point.attr_i64("x").unwrap() as f64 * 100.0 / w as f64;
+            let actual_y = point.attr_i64("y").unwrap() as f64 * 50.0 / h as f64;
+            assert!((actual_x - x).abs() < 0.001 && (actual_y - y).abs() < 0.001);
+        }
+        let line = properties.child("ln").unwrap();
+        assert_eq!(line.attr_i64("w"), Some(9525 * width));
+        assert_eq!(line.attr("cap"), Some("flat"));
+        assert!(line.child("miter").is_some());
+        let color = line.path(&["solidFill", "srgbClr"]).unwrap();
+        assert_eq!(color.attr("val"), Some("A12BCD"));
+        if width > 8 {
+            assert_eq!(color.child_val("alpha"), Some("45000"));
+        } else {
+            assert!(color.child("alpha").is_none_or(|a| a.attr("val") == Some("100000")));
+        }
+    }
+}
+
+#[test]
+fn numeric_polyline_from_an_independent_package_is_scaled_into_editable_ink() {
+    for (width, alpha) in [(3, ""), (12, r#"<a:alpha val="45000"/>"#)] {
+        let xml = drawing()
+            .replace("w=\"28575\"", &format!("w=\"{}\"", width * 9525))
+            .replace(r#"<a:srgbClr val="A12BCD"/>"#, &format!(r#"<a:srgbClr val="A12BCD">{alpha}</a:srgbClr>"#));
+        let wb = read_drawing(&xml);
+        let shapes = &wb.sheet(0).unwrap().shapes;
+        assert_eq!(shapes.len(), 1);
+        let shape = &shapes[0];
+        assert_eq!(shape.kind, ShapeKind::Ink);
+        assert_eq!(points(shape), [[-10.0, 5.0], [50.0, 40.0], [90.0, 10.0]]);
+        assert_eq!(shape.line, Color::Rgb(0xA12BCD));
+        assert_eq!(shape.fill, Color::Rgb(width << 16));
+        assert_eq!((shape.anchor.dx, shape.anchor.dy), (20.0, 30.0));
+        assert_eq!((shape.anchor.width, shape.anchor.height), (100.0, 50.0));
+    }
+}
+
+#[test]
+fn imported_points_are_not_snapped_to_native_tenth_units() {
+    let xml = drawing().replace("w=\"200\"", "w=\"2000000\"").replace(
+        POINTS,
+        r#"<a:moveTo><a:pt x="2001" y="10"/></a:moveTo><a:lnTo><a:pt x="1000000" y="80"/></a:lnTo><a:lnTo><a:pt x="1800000" y="20"/></a:lnTo>"#,
+    );
+    let wb = read_drawing(&xml);
+    let shape = &wb.sheet(0).unwrap().shapes[0];
+    assert_eq!(shape.kind, ShapeKind::Ink);
+    let original = points(shape);
+    assert!((original[0][0] - 0.10005).abs() < 0.00000001, "an imported coordinate is not necessarily a native tenth-unit point");
+    let (reopened, _) = read_xlsx(&write_xlsx(&wb).unwrap()).unwrap();
+    let after = &reopened.sheet(0).unwrap().shapes[0];
+    assert_eq!(after.kind, ShapeKind::Ink);
+    for (actual, expected) in points(after).iter().zip(original) {
+        for axis in 0..2 {
+            // A saved DrawingML coordinate is quantized to one EMU, plus f32 model precision.
+            assert!((actual[axis] - expected[axis]).abs() < 0.00006);
+        }
+    }
+}
+
+#[test]
+fn unsupported_geometry_or_appearance_is_not_reclassified_as_editable_ink() {
+    let original = drawing();
+    let cases = [
+        ("formula coordinate", original.replace("x=\"-20\"", "x=\"wd2\"")),
+        ("nonfinite coordinate", original.replace("x=\"-20\"", "x=\"NaN\"")),
+        ("overflow coordinate", original.replace("x=\"-20\"", "x=\"9223372036854775808\"")),
+        ("zero path width", original.replace("w=\"200\"", "w=\"0\"")),
+        ("missing point", original.replace(r#"<a:pt x="100" y="80"/>"#, "")),
+        (
+            "curve",
+            original
+                .replace(r#"<a:lnTo><a:pt x="100" y="80"/></a:lnTo>"#, r#"<a:quadBezTo><a:pt x="40" y="20"/><a:pt x="100" y="80"/></a:quadBezTo>"#),
+        ),
+        ("closed path", original.replace("</a:path>", "<a:close/></a:path>")),
+        ("multiple paths", original.replace("</a:pathLst>", &format!("{PATH}{POINTS}</a:path></a:pathLst>"))),
+        ("filled path", original.replace("fill=\"none\"", "fill=\"norm\"")),
+        ("filled shape", original.replace("<a:noFill/>", "<a:solidFill><a:srgbClr val=\"112233\"/></a:solidFill>")),
+        ("rotation", original.replace("<a:xfrm>", "<a:xfrm rot=\"60000\">")),
+        ("reflection", original.replace("<a:xfrm>", "<a:xfrm flipH=\"1\">")),
+        ("square caps", original.replace("cap=\"flat\"", "cap=\"sq\"")),
+        ("round join", original.replace("<a:miter/>", "<a:round/>")),
+        ("dash", original.replace("</a:ln>", "<a:prstDash val=\"dash\"/></a:ln>")),
+        ("arrow", original.replace("</a:ln>", "<a:headEnd type=\"triangle\"/></a:ln>")),
+        (
+            "caption",
+            original.replace("</xdr:sp>", "<xdr:txBody><a:bodyPr/><a:lstStyle/><a:p><a:r><a:t>Caption</a:t></a:r></a:p></xdr:txBody></xdr:sp>"),
+        ),
+        ("fractional width", original.replace("w=\"28575\"", "w=\"33338\"")),
+        ("unsupported opacity", original.replace(r#"<a:srgbClr val="A12BCD"/>"#, r#"<a:srgbClr val="A12BCD"><a:alpha val="50000"/></a:srgbClr>"#)),
+    ];
+    for (name, xml) in cases {
+        let wb = read_drawing(&xml);
+        assert!(wb.sheet(0).unwrap().shapes.iter().all(|s| s.kind != ShapeKind::Ink), "{name} was silently converted to editable ink");
+    }
+}
+
+#[test]
+fn oversized_polyline_is_not_truncated_into_different_ink() {
+    let mut commands = String::from(r#"<a:moveTo><a:pt x="0" y="0"/></a:moveTo>"#);
+    for _ in 0..20_000 {
+        commands.push_str(r#"<a:lnTo><a:pt x="100" y="80"/></a:lnTo>"#);
+    }
+    let wb = read_drawing(&drawing().replace(POINTS, &commands));
+    assert!(wb.sheet(0).unwrap().shapes.iter().all(|s| s.kind != ShapeKind::Ink));
+}
diff --git a/crates/xlsx/src/tests/literal_category_roundtrip.rs b/crates/xlsx/src/tests/literal_category_roundtrip.rs
new file mode 100644
index 0000000..c818de2
--- /dev/null
+++ b/crates/xlsx/src/tests/literal_category_roundtrip.rs
@@ -0,0 +1,59 @@
+//! Literal chart categories that contain a comma, a semicolon or a quote stay one category on save.
+
+use gridcraft_model::{Anchor, Chart, ChartKind, LegendPos, Series, Sheet, Workbook};
+use std::sync::Arc;
+
+use crate::{read_xlsx, write_xlsx};
+
+#[test]
+fn literal_category_with_separators_survives_save() {
+    // (typed array constant, what reading the saved file gives back)
+    let cats = [
+        (r#"{"a,b"}"#, r#"{"a,b"}"#),
+        (r#"{"a;b"}"#, r#"{"a;b"}"#),
+        (r#"{"red","blue"}"#, r#"{"red","blue"}"#),
+        (r#"{"say ""hi"", ok"}"#, r#"{"say ""hi"", ok"}"#),
+        (r#"{"a,b","c;d","e"}"#, r#"{"a,b","c;d","e"}"#),
+        (r#"{ "Jan" , "Feb, Mar" ; Apr }"#, r#"{"Jan","Feb, Mar","Apr"}"#),
+    ];
+    let mut wb = Workbook::default();
+    let mut s = Sheet::new("Data");
+    let series: Vec<Series> = cats
+        .iter()
+        .map(|(c, _)| Series {
+            name: Some("North, South".into()),
+            categories: Some((*c).into()),
+            values: "{1,2,3}".into(),
+            bubble_sizes: None,
+            color: None,
+            secondary: false,
+            kind: None,
+            smooth: false,
+            trendlines: Vec::new(),
+        })
+        .collect();
+    s.charts.push(Chart {
+        id: 1,
+        kind: ChartKind::ColumnClustered,
+        anchor: Anchor { cell: gridcraft_core::CellRef::new(0, 3), width: 480.0, height: 300.0, ..Anchor::default() },
+        title: None,
+        series,
+        legend: LegendPos::Bottom,
+        data_labels: false,
+        gridlines: true,
+        style: 2,
+        x_title: None,
+        y_title: None,
+        source: None,
+        by_rows: false,
+        pivot: None,
+    });
+    wb.sheets = vec![Arc::new(s)];
+    let bytes = write_xlsx(&wb).unwrap();
+    let (back, _rep) = read_xlsx(&bytes).unwrap();
+    let saved = &back.sheets[0].charts[0].series;
+    for (i, (_, want)) in cats.iter().enumerate() {
+        assert_eq!(saved[i].categories.as_deref(), Some(*want));
+        assert_eq!(saved[i].name.as_deref(), Some("North, South"));
+    }
+}
diff --git a/crates/xlsx/src/tests/malformed.rs b/crates/xlsx/src/tests/malformed.rs
index b14e53a..4700f8b 100644
--- a/crates/xlsx/src/tests/malformed.rs
+++ b/crates/xlsx/src/tests/malformed.rs
@@ -193,3 +193,19 @@ fn hostile_protected_ranges_stay_locked() {
         assert!(!matches!(h.verify("password"), Ok(true)), "{}", r.title);
     }
 }
+
+#[test]
+fn hyperlinks_past_the_cell_cap_are_reported() {
+    // A styles part, so the only possible warning is the hyperlink one.
+    let parts = [("xl/styles.xml", r#"<styleSheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"/>"#)];
+    let rels = r#"<Relationship Id="rId2" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/styles" Target="styles.xml"/>"#;
+    let body = r#"<sheetData/><hyperlinks><hyperlink ref="A1:A12000" location="x"/></hyperlinks>"#;
+    let (wb, rep) = read_xlsx(&minimal(body, &parts, rels, "")).unwrap();
+    assert_eq!(wb.sheet(0).unwrap().hyperlinks.len(), 10_000);
+    assert!(rep.warnings.iter().any(|w| w.contains("hyperlinks past the first 10000 cells were dropped")), "{:?}", rep.warnings);
+    // A small list reads in full with no warning.
+    let body = r#"<sheetData/><hyperlinks><hyperlink ref="A1:A3" location="x"/></hyperlinks>"#;
+    let (wb, rep) = read_xlsx(&minimal(body, &parts, rels, "")).unwrap();
+    assert_eq!(wb.sheet(0).unwrap().hyperlinks.len(), 3);
+    assert!(rep.warnings.is_empty(), "{:?}", rep.warnings);
+}
diff --git a/crates/xlsx/src/tests/mod.rs b/crates/xlsx/src/tests/mod.rs
index d5d2f2f..517113d 100644
--- a/crates/xlsx/src/tests/mod.rs
+++ b/crates/xlsx/src/tests/mod.rs
@@ -1,15 +1,19 @@
 //! Integration-style tests: round trips, hand-written fixtures, hostile input and CSV.
 
 mod array_export;
+mod chart_bool_default;
 mod csv_tests;
 mod encrypted_tests;
 mod fixtures;
+mod ink_roundtrip;
+mod literal_category_roundtrip;
 mod malformed;
 mod ods_tests;
 mod passthrough_tests;
 mod pivot_tests;
 mod richdata_tests;
 mod roundtrip;
+mod sheet_names;
 mod smooth_roundtrip;
 mod trendline_roundtrip;
 mod xls_tests;
diff --git a/crates/xlsx/src/tests/passthrough_tests.rs b/crates/xlsx/src/tests/passthrough_tests.rs
index 4cde9d6..aac9b6b 100644
--- a/crates/xlsx/src/tests/passthrough_tests.rs
+++ b/crates/xlsx/src/tests/passthrough_tests.rs
@@ -483,3 +483,41 @@ fn kept_vml_drawings_are_charged_to_the_kept_total() {
     let (wb, _) = read_xlsx(&rich_package_with(CONTENT_TYPES, true)).unwrap();
     assert!(wb.sheets.iter().all(|s| s.preserved.as_ref().is_some_and(|p| p.vml.is_some())));
 }
+
+#[test]
+fn file_version_and_calc_features_survive_a_save() {
+    // Excel trusts the saved cell values only when workbook.xml carries both <fileVersion> and the
+    // calcFeatures extension; without them it recalculates everything on open (#799).
+    let calc_features = r#"<ext uri="{B58B0392-4F1F-4190-BB64-5DF3571DCE5F}" xmlns:xcalcf="http://schemas.microsoft.com/office/spreadsheetml/2018/calcfeatures"><xcalcf:calcFeatures><xcalcf:feature name="microsoft.com:RD"/><xcalcf:feature name="microsoft.com:Single"/><xcalcf:feature name="microsoft.com:FV"/><xcalcf:feature name="microsoft.com:CNMTM"/><xcalcf:feature name="microsoft.com:LET_WF"/><xcalcf:feature name="microsoft.com:ARRAYTEXT_WF"/></xcalcf:calcFeatures></ext>"#;
+    let workbook = format!(
+        r#"<?xml version="1.0"?><workbook xmlns="{NS_MAIN}" xmlns:r="{NS_R}"><fileVersion appName="xl" lastEdited="7" lowestEdited="7" rupBuild="11008"/><workbookPr/><sheets><sheet name="A" sheetId="1" r:id="rId1"/></sheets><calcPr calcId="191029"/><extLst><ext uri="{{140A7094-0E35-4892-8432-C4D2E57EDEB5}}" xmlns:x15="http://schemas.microsoft.com/office/spreadsheetml/2010/11/main"><x15:workbookPr chartTrackingRefBase="1"/></ext>{calc_features}</extLst></workbook>"#
+    );
+    let sheet = format!(
+        r#"<?xml version="1.0"?><worksheet xmlns="{NS_MAIN}"><sheetData><row r="1"><c r="A1"><v>1</v></c><c r="B1"><f>A1*2</f><v>2</v></c></row></sheetData></worksheet>"#
+    );
+    let bytes = make_zip(&[
+        ("[Content_Types].xml", super::CT.as_bytes()),
+        ("_rels/.rels", super::ROOT_RELS.as_bytes()),
+        ("xl/workbook.xml", workbook.as_bytes()),
+        ("xl/_rels/workbook.xml.rels", rels(&[("rId1", "worksheet", "worksheets/sheet1.xml")]).as_bytes()),
+        ("xl/worksheets/sheet1.xml", sheet.as_bytes()),
+    ]);
+    let (wb, _) = read_xlsx(&bytes).unwrap();
+    // Twice: what was kept on the first save is read back and kept again.
+    let (again, _) = read_xlsx(&write_xlsx(&wb).unwrap()).unwrap();
+    for saved in [write_xlsx(&wb).unwrap(), write_xlsx(&again).unwrap()] {
+        let u = Unpacked::new(&saved);
+        u.assert_valid();
+        let text = u.text("xl/workbook.xml");
+        let root = xml::parse(text.as_bytes()).unwrap();
+        // Schema order: fileVersion is the first child of <workbook>, extLst the last.
+        assert_eq!(root.children.first().map(|e| e.name.as_str()), Some("fileVersion"), "{text}");
+        assert_eq!(root.children.last().map(|e| e.name.as_str()), Some("extLst"), "{text}");
+        assert!(text.contains(r#"<fileVersion appName="xl" lastEdited="7" lowestEdited="7" rupBuild="11008"/>"#), "{text}");
+        assert!(text.contains(&format!("<extLst>{calc_features}</extLst>")), "{text}");
+    }
+
+    // A workbook that had neither gets neither.
+    let plain = Unpacked::new(&write_xlsx(&gridcraft_model::Workbook::new()).unwrap()).text("xl/workbook.xml");
+    assert!(!plain.contains("fileVersion") && !plain.contains("extLst"), "{plain}");
+}
diff --git a/crates/xlsx/src/tests/pivot_tests.rs b/crates/xlsx/src/tests/pivot_tests.rs
index c854432..0c845aa 100644
--- a/crates/xlsx/src/tests/pivot_tests.rs
+++ b/crates/xlsx/src/tests/pivot_tests.rs
@@ -109,6 +109,8 @@ fn workbook() -> Workbook {
         show_headers: false,
         last_range: Some(rr("A2:H12")),
         calculated_fields: vec![],
+        values_on_rows: false,
+        values_position: None,
     };
     // Pivot 2: table source, date grouping on two levels, show-values-as, multi-select page
     // filter and a hidden-items filter on a column field.
@@ -166,6 +168,8 @@ fn workbook() -> Workbook {
         show_headers: true,
         last_range: Some(rr("K2:Z30")),
         calculated_fields: vec![],
+        values_on_rows: false,
+        values_position: None,
     };
     // Pivot 3: defaults, defined-name source, compact.
     let p3 = PivotTable {
@@ -508,3 +512,76 @@ fn calculated_fields_round_trip() {
         assert_eq!(a, b, "pivot {} differs", a.name);
     }
 }
+
+/// The `x` attributes of an axis list (`rowFields`/`colFields`) in a pivotTable part.
+fn axis_xs(table: &str, tag: &str) -> Vec<i64> {
+    let Some(start) = table.find(&format!("<{tag} ")) else { return vec![] };
+    let end = table[start..].find(&format!("</{tag}>")).map_or(table.len(), |e| start + e);
+    table[start..end].split("<field x=\"").skip(1).filter_map(|s| s.split('"').next()?.parse().ok()).collect()
+}
+
+#[test]
+fn values_on_rows_round_trip() {
+    let mut wb = workbook();
+    {
+        let p = wb.sheet_mut(1).unwrap().pivots.get_mut(1).unwrap();
+        p.values_on_rows = true;
+        p.values_position = Some(1);
+    }
+    let bytes = write_xlsx(&wb).unwrap();
+    let parts = unzip(&bytes);
+    let t2 = String::from_utf8(parts.get("xl/pivotTables/pivotTable2.xml").unwrap().clone()).unwrap();
+    assert!(t2.contains(" dataOnRows=\"1\""), "{t2}");
+    // Σ Values (-2) between the two row fields; Columns keep only Product.
+    let rows = axis_xs(&t2, "rowFields");
+    assert_eq!(rows.len(), 3, "{t2}");
+    assert_eq!(rows[1], -2, "{t2}");
+    assert!(!axis_xs(&t2, "colFields").contains(&-2), "{t2}");
+    assert!(t2.contains("firstDataRow=\"2\" firstDataCol=\"3\""), "{t2}");
+    let (back, report) = read_xlsx(&bytes).unwrap();
+    assert!(report.warnings.iter().all(|w| !w.to_lowercase().contains("pivot")), "{:?}", report.warnings);
+    assert_eq!(back.sheet(1).unwrap().pivots, wb.sheet(1).unwrap().pivots);
+
+    // After the last row field.
+    wb.sheet_mut(1).unwrap().pivots[1].values_position = None;
+    let bytes = write_xlsx(&wb).unwrap();
+    let t2 = String::from_utf8(unzip(&bytes).get("xl/pivotTables/pivotTable2.xml").unwrap().clone()).unwrap();
+    assert_eq!(axis_xs(&t2, "rowFields").last(), Some(&-2), "{t2}");
+    let (back, _) = read_xlsx(&bytes).unwrap();
+    assert_eq!(back.sheet(1).unwrap().pivots, wb.sheet(1).unwrap().pivots);
+
+    // Σ Values in Columns is written after the last column field, its only place in the layout.
+    {
+        let p = wb.sheet_mut(1).unwrap().pivots.get_mut(1).unwrap();
+        p.values_on_rows = false;
+        p.values_position = Some(0);
+    }
+    let bytes = write_xlsx(&wb).unwrap();
+    let t2 = String::from_utf8(unzip(&bytes).get("xl/pivotTables/pivotTable2.xml").unwrap().clone()).unwrap();
+    assert!(!t2.contains("dataOnRows"), "{t2}");
+    assert_eq!(axis_xs(&t2, "colFields").last(), Some(&-2), "{t2}");
+    let (back, _) = read_xlsx(&bytes).unwrap();
+    assert_eq!(back.sheet(1).unwrap().pivots[1].values_position, None);
+}
+
+#[test]
+fn values_ahead_of_column_fields_read_last() {
+    let table = r#"<pivotTableDefinition name="ValuesFirst" cacheId="1"><location ref="C1:F4"/><pivotFields><pivotField axis="axisCol"><items><item x="0"/><item x="1"/><item t="default"/></items></pivotField><pivotField dataField="1"/></pivotFields><colFields count="2"><field x="-2"/><field x="0"/></colFields><dataFields><dataField name="Sum of V" fld="1"/><dataField name="Count of V" fld="1" subtotal="count"/></dataFields></pivotTableDefinition>"#;
+    let (wb, _) = read_xlsx(&with_pivot(table, Some(GOOD_CACHE))).unwrap();
+    let pt = &wb.sheet(0).unwrap().pivots[0];
+    assert_eq!((pt.columns.len(), pt.values.len()), (1, 2));
+    assert!(!pt.values_on_rows);
+    assert_eq!(pt.values_position, None);
+}
+
+#[test]
+fn data_on_rows_with_one_value_field_reads_without_warning() {
+    let table = r#"<pivotTableDefinition name="OneValue" cacheId="1" dataOnRows="1"><location ref="C1:D4"/><pivotFields><pivotField axis="axisRow"><items><item x="0"/><item x="1"/><item t="default"/></items></pivotField><pivotField dataField="1"/></pivotFields><rowFields><field x="0"/></rowFields><dataFields><dataField name="Total" fld="1"/></dataFields></pivotTableDefinition>"#;
+    let (wb, report) = read_xlsx(&with_pivot(table, Some(GOOD_CACHE))).unwrap();
+    assert!(report.warnings.iter().all(|w| !w.contains("values on rows")), "{:?}", report.warnings);
+    let pt = &wb.sheet(0).unwrap().pivots[0];
+    assert!(pt.values_on_rows);
+    assert_eq!(pt.values_position, None);
+    let (back, _) = read_xlsx(&write_xlsx(&wb).unwrap()).unwrap();
+    assert!(back.sheet(0).unwrap().pivots[0].values_on_rows);
+}
diff --git a/crates/xlsx/src/tests/roundtrip.rs b/crates/xlsx/src/tests/roundtrip.rs
index 9601572..d214fd2 100644
--- a/crates/xlsx/src/tests/roundtrip.rs
+++ b/crates/xlsx/src/tests/roundtrip.rs
@@ -204,9 +204,9 @@ fn sample() -> Workbook {
             security_descriptor: None,
         },
     ];
-    s.hyperlinks.insert(at("A2"), Hyperlink { target: "https://example.com/?a=1&b=2".into(), tooltip: Some("go".into()) });
-    s.hyperlinks.insert(at("A3"), Hyperlink { target: "'Data & Stuff'!B2".into(), tooltip: None });
-    s.hyperlinks.insert(at("A4"), Hyperlink { target: "mailto:me@example.com".into(), tooltip: None });
+    s.hyperlinks.insert(at("A2"), Hyperlink { target: "https://example.com/?a=1&b=2".into(), tooltip: Some("go".into()), external: true });
+    s.hyperlinks.insert(at("A3"), Hyperlink { target: "'Data & Stuff'!B2".into(), tooltip: None, external: false });
+    s.hyperlinks.insert(at("A4"), Hyperlink { target: "mailto:me@example.com".into(), tooltip: None, external: true });
     s.comments.insert(
         at("B2"),
         Comment {
@@ -988,6 +988,42 @@ fn table_newline_column_and_backslash_name_survive() {
     assert!(gridcraft_formula::parse("COUNTA(\\_Prime.1[Name])").is_ok(), "backslash table name parses as a structured reference");
 }
 
+/// A table that is only a header row and a totals row (Insert Table on one row, then Total
+/// Row) is written like the header-only and one-data-row shapes, not dropped on save.
+#[test]
+fn header_and_totals_table_without_data_row_survives() {
+    let mut wb = Workbook::new();
+    let s = wb.sheet_mut(0).unwrap();
+    s.tables.push(Table {
+        id: 1,
+        name: "Table1".into(),
+        range: rr("A1:B2"),
+        header_row: true,
+        totals_row: true,
+        columns: vec![
+            TableColumn { name: "Name".into(), totals: TotalsFn::None, totals_label: Some("Total".into()), formula: None },
+            TableColumn { name: "Amount".into(), totals: TotalsFn::Sum, totals_label: None, formula: None },
+        ],
+        style: "TableStyleMedium2".into(),
+        banded_rows: true,
+        banded_cols: false,
+        first_col: true,
+        last_col: true,
+        filter_button: true,
+        filter: vec![],
+    });
+    let (back, report) = read_xlsx(&write_xlsx(&wb).unwrap()).unwrap();
+    assert!(report.warnings.is_empty(), "{:?}", report.warnings);
+    let tables = &back.sheet(0).unwrap().tables;
+    assert_eq!(tables.len(), 1);
+    let t = &tables[0];
+    assert_eq!((t.name.as_str(), t.range.a1(), t.header_row, t.totals_row), ("Table1", "A1:B2".to_string(), true, true));
+    assert_eq!((t.style.as_str(), t.banded_rows, t.first_col, t.last_col), ("TableStyleMedium2", true, true, true));
+    assert_eq!(t.columns[0].totals_label.as_deref(), Some("Total"));
+    assert_eq!(t.columns[1].totals, TotalsFn::Sum);
+    assert_eq!(back.sheet(0).unwrap().value(at("A1")), Value::text("Name"));
+}
+
 /// Templates and macro-enabled files differ from `.xlsx` only in the workbook part's content
 /// type; a template saved with the workbook type is rejected by Excel.
 #[test]
@@ -1014,3 +1050,88 @@ fn package_kind_sets_workbook_content_type() {
     }
     assert_eq!(crate::XlsxKind::from_path("noext"), crate::XlsxKind::Workbook);
 }
+
+/// The workbook's default font (`fonts[0]`, the Normal style's) is what every default-formatted
+/// cell shows, typed or empty; saving keeps it instead of resetting it to Calibri 11 (#805).
+#[test]
+fn default_font_survives_a_round_trip() {
+    let styles = |font0: &str| {
+        format!(
+            r#"<styleSheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"><fonts count="2"><font>{font0}</font><font><b/><sz val="14"/><color theme="1"/><name val="Arial"/><family val="2"/></font></fonts>
+            <fills count="2"><fill><patternFill patternType="none"/></fill><fill><patternFill patternType="gray125"/></fill></fills><borders count="1"><border><left/><right/><top/><bottom/><diagonal/></border></borders>
+            <cellStyleXfs count="1"><xf numFmtId="0" fontId="0" fillId="0" borderId="0"/></cellStyleXfs>
+            <cellXfs count="2"><xf numFmtId="0" fontId="0" fillId="0" borderId="0" xfId="0"/><xf numFmtId="0" fontId="1" fillId="0" borderId="0" xfId="0" applyFont="1"/></cellXfs>
+            <cellStyles count="1"><cellStyle name="Normal" xfId="0" builtinId="0"/></cellStyles></styleSheet>"#
+        )
+    };
+    let rels = r#"<Relationship Id="rId2" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/styles" Target="styles.xml"/>"#;
+    let body = r#"<sheetData><row r="1"><c r="A1" t="inlineStr"><is><t>typed text</t></is></c><c r="B1" s="1"><v>1</v></c></row></sheetData>"#;
+    let font0 = |bytes: &[u8]| {
+        let mut pkg = Package::open(bytes).unwrap();
+        let st = pkg.read_xml("xl/styles.xml").unwrap().unwrap();
+        let f = st.child("fonts").unwrap().kids("font").next().unwrap().clone();
+        let val = |n: &str| f.child(n).and_then(|e| e.attr("val")).map(str::to_string);
+        (val("sz"), val("name"), val("family"), val("scheme"))
+    };
+
+    let file =
+        super::minimal(body, &[("xl/styles.xml", &styles(r#"<sz val="10"/><color theme="1"/><name val="Arial"/><family val="2"/>"#))], rels, "");
+    let (wb, _) = read_xlsx(&file).unwrap();
+    let saved = write_xlsx(&wb).unwrap();
+    assert_eq!(font0(&saved), (Some("10".into()), Some("Arial".into()), Some("2".into()), None));
+    let (back, _) = read_xlsx(&saved).unwrap();
+    let normal = &back.styles.get(StyleId::DEFAULT).font;
+    assert_eq!((normal.name.as_str(), normal.size), ("Arial", 10.0), "empty cells and new input take the Normal font");
+    let s = back.sheet(0).unwrap();
+    assert_eq!(s.cell(at("A1")).unwrap().style, StyleId::DEFAULT);
+    let b1 = &back.styles.get(s.cell(at("B1")).unwrap().style).font;
+    assert!(b1.bold && b1.size == 14.0, "an explicit font is still its own: {b1:?}");
+
+    // Excel's own Normal font follows the theme's body font; the scheme link survives too.
+    let file = super::minimal(
+        body,
+        &[("xl/styles.xml", &styles(r#"<name val="Calibri"/><family val="2"/><color theme="1"/><sz val="12"/><scheme val="minor"/>"#))],
+        rels,
+        "",
+    );
+    let saved = write_xlsx(&read_xlsx(&file).unwrap().0).unwrap();
+    assert_eq!(font0(&saved), (Some("12".into()), Some("Calibri".into()), Some("2".into()), Some("minor".into())));
+#[test]
+fn solid_data_bar_survives_with_sparklines_and_gradient_neighbours() {
+    let mut wb = Workbook::new();
+    let s = wb.sheet_mut(0).unwrap();
+    s.set_value(at("A1"), Value::Number(1.0));
+    let bar = |gradient: bool, max: CfValueKind| CfRule::DataBar {
+        min: CfValueKind::Min,
+        max,
+        color: Color::Rgb(0x638EC6),
+        gradient,
+        show_value: true,
+    };
+    let rules = [(true, "A1", CfValueKind::Max), (false, "B1", CfValueKind::Formula("$C$1".into())), (false, "D1:D3", CfValueKind::Number(9.0))];
+    for (i, (gradient, range, max)) in rules.into_iter().enumerate() {
+        s.cond_formats.push(CondFormat { ranges: vec![rr(range)], rule: bar(gradient, max), priority: i as u32 + 1, stop_if_true: false });
+    }
+    s.sparklines.push(Sparkline { cell: at("F1"), source: "A1:C1".into(), kind: SparklineKind::Line, color: Color::Rgb(0x376092), markers: false });
+    let bytes = write_xlsx(&wb).unwrap();
+    // x14 cfvo values are `xm:f` children; a `val` attribute there is not valid x14.
+    let (xml, _) = sheet1_xml(&bytes);
+    assert!(xml.contains("<x14:cfvo type=\"num\"><xm:f>9</xm:f></x14:cfvo>"), "{xml}");
+    let (back, rep) = read_xlsx(&bytes).unwrap();
+    assert!(rep.warnings.is_empty(), "{:?}", rep.warnings);
+    let b = &back.sheets[0];
+    assert_eq!(b.cond_formats, wb.sheets[0].cond_formats);
+    assert_eq!(b.sparklines.len(), 1);
+fn doc_props_keep_boundary_whitespace() {
+    let mut wb = Workbook::new();
+    wb.props = DocProps {
+        title: "  Title  ".into(),
+        subject: "\n".into(),
+        author: "\tMe\t".into(),
+        company: " Co ".into(),
+        keywords: " a, b ".into(),
+        description: "\n  d\n".into(),
+    };
+    let (back, _) = read_xlsx(&write_xlsx(&wb).unwrap()).unwrap();
+    assert_eq!(back.props, wb.props);
+}
diff --git a/crates/xlsx/src/tests/sheet_names.rs b/crates/xlsx/src/tests/sheet_names.rs
new file mode 100644
index 0000000..a557bd8
--- /dev/null
+++ b/crates/xlsx/src/tests/sheet_names.rs
@@ -0,0 +1,23 @@
+//! Sheet names XLSX cannot hold are refused on export instead of breaking formulas on reopen.
+
+use std::sync::Arc;
+
+use gridcraft_model::{Sheet, Workbook};
+
+use crate::{IoError, write_xlsx};
+
+fn book(names: &[&str]) -> Workbook {
+    let mut wb = Workbook::new();
+    wb.sheets = names.iter().map(|n| Arc::new(Sheet::new(*n))).collect();
+    wb
+}
+
+#[test]
+fn unrepresentable_sheet_names_are_refused() {
+    let long_a = format!("{}X", "A".repeat(31));
+    let long_b = format!("{}Y", "A".repeat(31));
+    for names in [vec!["Data", "a/b"], vec![long_a.as_str(), long_b.as_str()], vec!["Data", "data"], vec!["Data", ""]] {
+        assert!(matches!(write_xlsx(&book(&names)), Err(IoError::Format(_))), "{names:?}");
+    }
+    assert!(write_xlsx(&book(&["Data", "Other"])).is_ok());
+}
diff --git a/crates/xlsx/src/tests/xls_tests.rs b/crates/xlsx/src/tests/xls_tests.rs
index fd37795..38820a1 100644
--- a/crates/xlsx/src/tests/xls_tests.rs
+++ b/crates/xlsx/src/tests/xls_tests.rs
@@ -330,11 +330,12 @@ fn reads_values_formulas_formats_and_layout() {
         // Shared formula: relative offsets resolve per cell.
         assert_eq!(ftext(&wb, "B5").as_deref(), Some("A5*10"));
         assert_eq!(ftext(&wb, "B6").as_deref(), Some("A6*10"));
-        // Array formula: the anchor holds it, the other cell keeps its value.
+        // Array formula: the anchor holds it; the other cell's cached result is dropped so that
+        // the formula fills the range on recalculation (as when an .xlsx is read, #156).
         let c5 = wb.sheets[0].cell(CellRef::parse("C5").unwrap()).unwrap().formula.clone().unwrap();
         assert_eq!((c5.text.as_str(), c5.array), ("A5:A6*2", Some(RangeRef::parse("C5:C6").unwrap())));
         assert_eq!(ftext(&wb, "C6"), None);
-        assert_eq!(v(&wb, 0, "C6"), Value::Number(4.0));
+        assert_eq!(v(&wb, 0, "C6"), Value::Empty);
         // Number formats, merges, sizes, names, print area; embedded chart records ignored.
         let sh = &wb.sheets[0];
         assert_eq!(wb.styles.get(sh.style_id(CellRef::parse("A4").unwrap())).num_fmt.as_str(), "yyyy-mm-dd");
@@ -358,6 +359,21 @@ fn reads_values_formulas_formats_and_layout() {
     assert_eq!(wb.date_system, DateSystem::D1904);
 }
 
+#[test]
+fn text_result_of_a_formula_kept_as_its_value() {
+    // A what-if data table cell ({=TABLE(B1,)}) can't be imported as a formula, so its saved result
+    // is kept. With the default XF the cell is blank until the String record brings the text.
+    let table = cat(&[&[0x02], &u16s(&[0, 0])]);
+    let sheet = cat(&[&bof(0x0010), &formula(0, 0, special(0, 0), &table), &rec(0x0207, &xlstr("103a")), &eof()]);
+    let boundsheet = |pos: u32| rec(0x0085, &cat(&[&pos.to_le_bytes(), &[0, 0, 6, 0], b"Sheet1"]));
+    let len = cat(&[&bof(0x0005), &boundsheet(0), &eof()]).len() as u32;
+    let stream = cat(&[&bof(0x0005), &boundsheet(len), &eof(), &sheet]);
+    let (wb, report) = read_xls(&compound("Workbook", &stream)).unwrap();
+    assert!(report.warnings.iter().any(|w| w.contains("what-if data tables")), "{:?}", report.warnings);
+    assert_eq!(ftext(&wb, "A1"), None);
+    assert_eq!(v(&wb, 0, "A1"), Value::from("103a"));
+}
+
 #[test]
 fn refuses_encrypted_old_and_foreign_files() {
     // FILEPASS in the globals: an encrypted workbook.
@@ -476,3 +492,99 @@ fn sheets_share_one_record_budget() {
     let err = read_xls(&compound("Workbook", &dup)).unwrap_err().to_string();
     assert!(err.contains("same substream"), "{err}");
 }
+
+#[test]
+fn formulas_using_a_skipped_name_keep_their_saved_results() {
+    // Lbl "ExtRange" = [Source.xlsx]Sheet1!$A$1:$A$3 (PtgArea3d through an external SupBook),
+    // "Local" = Sheet1!$A$1 and "Twice" = ExtRange*2. Only the first is skipped on import; a
+    // name that uses it is still read as it was.
+    let ext = cat(&[&[0x3B], &1u16.to_le_bytes(), &u16s(&[0, 2, 0, 0])]);
+    let local = cat(&[&[0x3A], &0u16.to_le_bytes(), &u16s(&[0, 0])]);
+    let twice = cat(&[&[0x23], &1u32.to_le_bytes(), &ptg_int(2), &[0x05]]);
+    let lbl = |name: &str, rgce: &[u8]| {
+        rec(0x0018, &cat(&[&u16s(&[0]), &[0, name.len() as u8], &u16s(&[rgce.len() as u16, 0, 0]), &[0; 4], &[0], name.as_bytes(), rgce]))
+    };
+    let boundsheet = |pos: u32| rec(0x0085, &cat(&[&pos.to_le_bytes(), &[0, 0, 6, 0], b"Sheet1"]));
+    let globals = |pos: u32| {
+        cat(&[
+            &bof(0x0005),
+            &boundsheet(pos),
+            &rec(0x01AE, &u16s(&[1, 0x0401])),
+            &rec(0x01AE, &cat(&[&u16s(&[1]), &xlstr("Source.xlsx"), &xlstr("Sheet1")])),
+            &rec(0x0017, &cat(&[&u16s(&[2]), &u16s(&[0, 0, 0]), &u16s(&[1, 0, 0])])),
+            &lbl("ExtRange", &ext),
+            &lbl("Local", &local),
+            &lbl("Twice", &twice),
+            &eof(),
+        ])
+    };
+    let sum_ext = cat(&[&[0x43], &1u32.to_le_bytes(), &[0x22, 1], &4u16.to_le_bytes()]);
+    let local_x2 = cat(&[&[0x43], &2u32.to_le_bytes(), &ptg_int(2), &[0x05]]);
+    let sheet = cat(&[
+        &bof(0x0010),
+        &rec(0x0203, &cat(&[&cell(0, 0, 0), &10.0f64.to_le_bytes()])),
+        &formula(5, 1, num(60.0), &sum_ext),
+        &formula(6, 1, num(20.0), &local_x2),
+        &eof(),
+    ]);
+    let pos = globals(0).len() as u32;
+    let (wb, report) = read_xls(&compound("Workbook", &cat(&[&globals(pos), &sheet]))).unwrap();
+    let names: Vec<_> = wb.names.iter().map(|n| (n.name.as_str(), n.formula.as_str())).collect();
+    assert_eq!(names, [("Local", "Sheet1!$A$1"), ("Twice", "ExtRange*2")]);
+    assert_eq!(ftext(&wb, "B6"), None);
+    assert_eq!(v(&wb, 0, "B6"), Value::Number(60.0));
+    assert_eq!(ftext(&wb, "B7").as_deref(), Some("Local*2"));
+    assert!(report.warnings.iter().any(|w| w.contains("defined names") && w.contains("saved results")), "{:?}", report.warnings);
+fn reads_iterative_calculation_settings() {
+    // CalcMode, CalcCount, CalcIter and CalcDelta repeat in every worksheet substream; here only
+    // the first sheet carries them, so the sheet after it must not reset them to the defaults.
+    // CalcPrecision sits in the globals.
+    let calc = cat(&[&rec(0x000D, &u16s(&[0])), &rec(0x000C, &u16s(&[50])), &rec(0x0011, &u16s(&[1])), &rec(0x0010, &0.01f64.to_le_bytes())]);
+    let sheet1 = cat(&[&bof(0x0010), &calc, &eof()]);
+    let sheet2 = cat(&[&bof(0x0010), &eof()]);
+    let boundsheet = |pos: u32, name: &str| rec(0x0085, &cat(&[&pos.to_le_bytes(), &[0, 0, name.len() as u8, 0], name.as_bytes()]));
+    let globals = |p1: u32, p2: u32| cat(&[&bof(0x0005), &rec(0x000E, &u16s(&[0])), &boundsheet(p1, "A"), &boundsheet(p2, "B"), &eof()]);
+    let p1 = globals(0, 0).len() as u32;
+    let p2 = p1 + sheet1.len() as u32;
+    let (wb, _) = read_xls(&compound("Workbook", &cat(&[&globals(p1, p2), &sheet1, &sheet2]))).unwrap();
+    assert!(wb.calc.iterative);
+    assert_eq!((wb.calc.max_iterations, wb.calc.max_change), (50, 0.01));
+    assert_eq!(wb.calc.mode, gridcraft_model::CalcMode::Manual);
+    assert!(wb.calc.precision_as_displayed);
+    // Without the records: Excel's defaults, iteration off.
+    let (wb, _) = read_xls(&compound("Workbook", &sample(false))).unwrap();
+    assert_eq!(wb.calc, gridcraft_model::CalcSettings::default());
+fn a_format_shorter_than_its_count_keeps_its_characters() {
+    // A FORMAT whose cch is one more than the characters in the record (seen in real files):
+    // Excel opens them, the record's characters are the format code.
+    let short = rec(0x041E, &cat(&[&165u16.to_le_bytes(), &6u16.to_le_bytes(), &[0], b"0.000"]));
+    let xf = |ifmt: u16| rec(0x00E0, &cat(&[&u16s(&[0, ifmt, 0]), &[0; 14]]));
+    let globals = |pos: u32| {
+        cat(&[
+            &bof(0x0005),
+            &short,
+            &rec(0x041E, &cat(&[&164u16.to_le_bytes(), &xlstr("yyyy-mm-dd")])),
+            &xf(0),
+            &xf(164),
+            &xf(165),
+            &rec(0x0085, &cat(&[&pos.to_le_bytes(), &[0, 0, 6, 0], b"Sheet1"])),
+            &eof(),
+        ])
+    };
+    let sheet = cat(&[
+        &bof(0x0010),
+        &rec(0x0203, &cat(&[&cell(0, 0, 0), &7.0f64.to_le_bytes()])),
+        &rec(0x0203, &cat(&[&cell(1, 0, 1), &0.0f64.to_le_bytes()])),
+        &rec(0x0203, &cat(&[&cell(2, 0, 2), &1.25f64.to_le_bytes()])),
+        &eof(),
+    ]);
+    let stream = cat(&[&globals(globals(0).len() as u32), &sheet]);
+    let (wb, report) = read_xls(&compound("Workbook", &stream)).unwrap();
+    let sh = &wb.sheets[0];
+    let fmt = |a1: &str| wb.styles.get(sh.style_id(CellRef::parse(a1).unwrap())).num_fmt.as_str().to_string();
+    assert_eq!(v(&wb, 0, "A1"), Value::Number(7.0));
+    assert_eq!(v(&wb, 0, "A3"), Value::Number(1.25));
+    assert_eq!(fmt("A2"), "yyyy-mm-dd");
+    assert_eq!(fmt("A3"), "0.000");
+    assert!(report.warnings.iter().any(|w| w.contains("declared length")), "{:?}", report.warnings);
+}
diff --git a/crates/xlsx/src/write.rs b/crates/xlsx/src/write.rs
index 9c117f4..dddba98 100644
--- a/crates/xlsx/src/write.rs
+++ b/crates/xlsx/src/write.rs
@@ -161,6 +161,30 @@ pub fn abs_range(r: &RangeRef) -> String {
     format!("${}${}:${}${}", c(r.start.col), r.start.row + 1, c(r.end.col), r.end.row + 1)
 }
 
+/// Refuses sheet names XLSX cannot hold. The reader repairs such names (cuts, strips, renames
+/// duplicates) but formulas keep the old spelling, so the saved file would turn into `#REF!`.
+fn check_sheet_names(wb: &Workbook) -> Result<(), IoError> {
+    let mut seen = std::collections::HashSet::new();
+    for sheet in &wb.sheets {
+        let name = &sheet.name;
+        let bad = if name.is_empty() {
+            Some("is blank")
+        } else if name.chars().count() > 31 {
+            Some("is longer than 31 characters")
+        } else if name.chars().any(|c| matches!(c, ':' | '\\' | '/' | '?' | '*' | '[' | ']')) {
+            Some("contains one of : \\ / ? * [ ]")
+        } else if !seen.insert(name.to_ascii_lowercase()) {
+            Some("is used by another sheet")
+        } else {
+            None
+        };
+        if let Some(why) = bad {
+            return Err(IoError::Format(format!("sheet name \"{name}\" {why}; rename the sheet before saving as XLSX")));
+        }
+    }
+    Ok(())
+}
+
 pub fn write_xlsx(wb: &Workbook, kind: XlsxKind) -> Result<Vec<u8>, IoError> {
     if wb.sheets.is_empty() {
         return Err(IoError::Format("a workbook needs at least one sheet".into()));
@@ -168,6 +192,7 @@ pub fn write_xlsx(wb: &Workbook, kind: XlsxKind) -> Result<Vec<u8>, IoError> {
     if wb.sheets.iter().any(|sheet| sheet.cell_pictures.keys().any(|c| sheet.cell(*c).is_some_and(|cell| cell.formula.is_some()))) {
         return Err(IoError::Format("a static cell picture cannot also contain a formula".into()));
     }
+    check_sheet_names(wb)?;
     let mut out = Out {
         parts: vec![],
         overrides: vec![],
@@ -270,6 +295,7 @@ pub fn write_xlsx(wb: &Workbook, kind: XlsxKind) -> Result<Vec<u8>, IoError> {
     }
 
     let mut w = format!("{XML_DECL}<workbook xmlns=\"{NS_MAIN}\" xmlns:r=\"{NS_REL}\">");
+    w.push_str(&crate::passthrough::workbook_elements(wb, "fileVersion"));
     w.push_str(if wb.date_system == gridcraft_core::DateSystem::D1904 { "<workbookPr date1904=\"1\"/>" } else { "<workbookPr/>" });
     if wb.protected_structure {
         let pw = wb.structure_password.as_ref().map(|h| crate::sheet_write::password_attrs(h, "workbook")).unwrap_or_default();
@@ -306,6 +332,10 @@ pub fn write_xlsx(wb: &Workbook, kind: XlsxKind) -> Result<Vec<u8>, IoError> {
     }
     w.push_str("/>");
     w.push_str(&pivots.workbook_xml(&mut wb_rels));
+    let exts = crate::passthrough::workbook_elements(wb, "ext");
+    if !exts.is_empty() {
+        let _ = write!(w, "<extLst>{exts}</extLst>");
+    }
     w.push_str("</workbook>");
 
     // Workbook-level parts.
diff --git a/crates/xlsx/src/xls/formula.rs b/crates/xlsx/src/xls/formula.rs
index 87a512c..3de8607 100644
--- a/crates/xlsx/src/xls/formula.rs
+++ b/crates/xlsx/src/xls/formula.rs
@@ -51,6 +51,8 @@ pub(super) struct Links {
     pub sheets: Vec<String>,
     /// Defined names (Lbl records), in order; `None` for names that can't be referenced.
     pub names: Vec<String>,
+    /// Per defined name: whether the import skips it (its formula can't be decoded).
+    pub skipped: Vec<bool>,
     pub books: Vec<SupBook>,
     pub xti: Vec<Xti>,
 }
@@ -330,13 +332,13 @@ pub(super) fn decode(rgce: &[u8], rgcb: &[u8], base: CellRef, mode: Mode, links:
                 }
             }
             0x23 => {
-                let i = t.u32()?;
-                let name = usize::try_from(i)
-                    .ok()
-                    .and_then(|i| i.checked_sub(1))
-                    .and_then(|i| links.names.get(i))
-                    .filter(|n| !n.is_empty())
-                    .ok_or(Unsupported("reference to a missing defined name"))?;
+                let i = usize::try_from(t.u32()?).ok().and_then(|i| i.checked_sub(1));
+                let name = i.and_then(|i| links.names.get(i)).filter(|n| !n.is_empty()).ok_or(Unsupported("reference to a missing defined name"))?;
+                // A cell using a name the import drops would calculate to #NAME?: keep its
+                // saved result instead, as for references to other workbooks.
+                if mode != Mode::Name && i.and_then(|i| links.skipped.get(i)) == Some(&true) {
+                    return Err(Unsupported("defined names GridCraft skipped"));
+                }
                 push(&mut stack, kids, Expr::Name(name.clone()))?;
             }
             0x24 | 0x2C => {
@@ -479,6 +481,7 @@ mod tests {
         Links {
             sheets: vec!["Sheet1".into(), "My Data".into()],
             names: vec!["Rate".into()],
+            skipped: vec![false],
             books: vec![
                 SupBook { internal: true, addin: false, names: vec![] },
                 SupBook { internal: false, addin: true, names: vec!["_xlfn.IFERROR".into()] },
diff --git a/crates/xlsx/src/xls/mod.rs b/crates/xlsx/src/xls/mod.rs
index c9aee66..dde8641 100644
--- a/crates/xlsx/src/xls/mod.rs
+++ b/crates/xlsx/src/xls/mod.rs
@@ -4,9 +4,10 @@
 //!
 //! Read: worksheets, shared strings, cell values, formulas (text and cached results, including
 //! shared and array formulas), number formats, the 1904 date system, merged cells, column
-//! widths, row heights, defined names, print areas and print titles. Everything else (fonts,
-//! fills, borders, charts, pictures, comments, conditional formats, validation, macros) is
-//! skipped with a warning. Encrypted workbooks and pre-BIFF8 versions are refused.
+//! widths, row heights, defined names, print areas, print titles and the calculation settings
+//! (mode, iteration, precision as displayed). Everything else (fonts, fills, borders, charts,
+//! pictures, comments, conditional formats, validation, macros) is skipped with a warning.
+//! Encrypted workbooks and pre-BIFF8 versions are refused.
 
 mod formula;
 mod ftab;
@@ -16,7 +17,7 @@ use std::collections::HashMap;
 use std::sync::Arc;
 
 use gridcraft_core::{CellRef, DateSystem, MAX_COLS, MAX_ROWS, RangeRef, Value};
-use gridcraft_model::{Cell, DefinedName, Formula, LineInfo, NumFmt, Sheet, Style, StyleId, Visibility, Workbook};
+use gridcraft_model::{CalcMode, CalcSettings, Cell, DefinedName, Formula, LineInfo, NumFmt, Sheet, Style, StyleId, Visibility, Workbook};
 
 use crate::cfb::Compound;
 use crate::tables::{builtin_format, col_width_to_px, pt_to_px};
@@ -123,6 +124,7 @@ struct Globals {
     sst: Vec<Arc<str>>,
     links: Links,
     names: Vec<Lbl>,
+    precision_as_displayed: bool,
 }
 
 /// Reads an Excel 97-2003 workbook. Inspect the report's warnings for what was skipped.
@@ -143,7 +145,7 @@ pub(crate) fn read_xls_with(bytes: &[u8], mut budget: Budget) -> Result<(Workboo
         }
     };
     let mut report = ReadReport::default();
-    let g = globals(&stream, &mut budget)?;
+    let g = globals(&stream, &mut budget, &mut report)?;
 
     let mut wb = Workbook::new();
     wb.sheets.clear();
@@ -175,18 +177,23 @@ pub(crate) fn read_xls_with(bytes: &[u8], mut budget: Budget) -> Result<(Workboo
             continue;
         }
         wb.check_sheet_name(&bs.name, None).map_err(invalid)?;
-        let Some(mut sheet) = worksheet(&stream, bs, &g, &styles, &mut budget, &mut report)? else {
+        let Some((mut sheet, calc)) = worksheet(&stream, bs, &g, &styles, &mut budget, &mut report)? else {
             report.warn("Dialog sheets and unreadable sheets were skipped.");
             model_index.push(None);
             continue;
         };
         sheet.visibility = bs.visibility;
+        // Every worksheet repeats the workbook's calculation settings; Excel applies the first.
+        if wb.sheets.is_empty() {
+            wb.calc = calc;
+        }
         model_index.push(Some(wb.sheets.len()));
         wb.sheets.push(Arc::new(sheet));
     }
     if wb.sheets.is_empty() {
         return Err(invalid("the workbook has no worksheets GridCraft can read"));
     }
+    wb.calc.precision_as_displayed = g.precision_as_displayed;
     defined_names(&g, &model_index, &mut wb, &mut report);
     wb.active_sheet = wb.sheets.iter().position(|s| s.visibility == Visibility::Visible).unwrap_or(0);
     // The overview comes first.
@@ -205,7 +212,7 @@ fn bof(rec: &Record<'_>) -> Result<(u16, u16), IoError> {
     Ok((c.u16()?, c.u16()?))
 }
 
-fn globals(stream: &[u8], budget: &mut Budget) -> Result<Globals, IoError> {
+fn globals(stream: &[u8], budget: &mut Budget, report: &mut ReadReport) -> Result<Globals, IoError> {
     let mut recs = Records::new(stream, 0);
     let first = recs.next_record()?.ok_or_else(|| invalid("empty Workbook stream"))?;
     let (vers, dt) = bof(&first)?;
@@ -247,9 +254,18 @@ fn globals(stream: &[u8], budget: &mut Budget) -> Result<Globals, IoError> {
                 g.sheets.push(BoundSheet { pos, name, visibility, kind });
             }
             0x0022 => g.date1904 = c.u16()? == 1,
+            0x000E => g.precision_as_displayed = c.u16()? == 0,
             0x041E => {
                 let ifmt = c.u16()?;
-                let code = c.string()?;
+                let cch = usize::from(c.u16()?);
+                let high = c.u8()? & 1 != 0;
+                // Some writers count one character more than the record holds; Excel opens
+                // those files, so keep the characters that are there.
+                let fit = c.remaining() / if high { 2 } else { 1 };
+                if cch > fit {
+                    report.warn("Some number formats were shorter than their declared length; the characters present were kept.");
+                }
+                let code = c.chars(cch.min(fit), high)?;
                 budget.text(code.len())?;
                 g.formats.insert(ifmt, code);
             }
@@ -297,6 +313,9 @@ fn globals(stream: &[u8], budget: &mut Budget) -> Result<Globals, IoError> {
             _ => {}
         }
     }
+    // The same test `defined_names` applies, before any cell formula is decoded.
+    let skipped = g.names.iter().map(|l| !l.rgce.is_empty() && decode(&l.rgce, &l.rgcb, CellRef::new(0, 0), Mode::Name, &g.links).is_err()).collect();
+    g.links.skipped = skipped;
     Ok(g)
 }
 
@@ -390,9 +409,12 @@ struct SheetState<'g> {
     shared: HashMap<CellRef, Parsed>,
     arrays: HashMap<CellRef, (RangeRef, Parsed)>,
     last_formula: Option<CellRef>,
-    pending_string: Option<CellRef>,
+    /// The cell waiting for its String record, with its style: a blank cell isn't stored, so a
+    /// formula kept as its value may have no cell to receive the text.
+    pending_string: Option<(CellRef, StyleId)>,
     dropped: usize,
     unsupported: Vec<&'static str>,
+    calc: CalcSettings,
 }
 
 impl SheetState<'_> {
@@ -462,7 +484,7 @@ fn worksheet(
     styles: &[StyleId],
     budget: &mut Budget,
     report: &mut ReadReport,
-) -> Result<Option<Sheet>, IoError> {
+) -> Result<Option<(Sheet, CalcSettings)>, IoError> {
     if bs.pos >= stream.len() {
         return Err(invalid(format!("sheet '{}' points outside the Workbook stream", bs.name)));
     }
@@ -483,6 +505,7 @@ fn worksheet(
         pending_string: None,
         dropped: 0,
         unsupported: vec![],
+        calc: CalcSettings::default(),
     };
     let mut depth = 1usize;
     while let Some(rec) = recs.next_record()? {
@@ -507,9 +530,9 @@ fn worksheet(
     }
     // Shared and array formulas: their definitions follow the first cell that uses them.
     let (arrays, shared) = (std::mem::take(&mut st.arrays), std::mem::take(&mut st.shared));
-    for p in std::mem::take(&mut st.pending) {
+    let pending = std::mem::take(&mut st.pending);
+    for p in &pending {
         if let Some((range, f)) = arrays.get(&p.anchor) {
-            // The other cells of an array formula keep only their values.
             if p.pos == p.anchor {
                 st.attach(p.pos, f, Mode::Cell, Some(*range));
             }
@@ -519,13 +542,23 @@ fn worksheet(
             st.unsupported("a shared formula that is missing from the file");
         }
     }
+    // The other cells of a legacy array formula hold only cached results: dropped, as when an
+    // .xlsx is read, so that the formula fills its range on recalculation. If the formula itself
+    // couldn't be imported, they keep their values.
+    for p in &pending {
+        let filled = st.sheet.cell(p.anchor).and_then(|c| c.formula.as_ref()).and_then(|f| f.array).is_some_and(|r| r.contains(p.pos));
+        if p.pos != p.anchor && filled {
+            let style = st.sheet.style_id(p.pos);
+            st.sheet.cells.set(p.pos, Cell { value: Value::Empty, formula: None, style });
+        }
+    }
     if st.dropped > 0 {
         report.warn(format!("{} cells outside the grid were skipped.", st.dropped));
     }
     for why in &st.unsupported {
         report.warn(format!("Some formulas use {why}; their saved results were kept as values."));
     }
-    Ok(Some(st.sheet))
+    Ok(Some((st.sheet, st.calc)))
 }
 
 fn sheet_record(rec: &Record<'_>, st: &mut SheetState<'_>, budget: &mut Budget, report: &mut ReadReport) -> Result<(), IoError> {
@@ -594,11 +627,13 @@ fn sheet_record(rec: &Record<'_>, st: &mut SheetState<'_>, budget: &mut Budget,
         }
         0x0006 => formula_cell(&mut c, st, budget)?,
         0x0207 => {
-            if let Some(pos) = st.pending_string.take() {
+            if let Some((pos, style)) = st.pending_string.take() {
                 let s = c.string()?;
                 budget.text(s.len())?;
                 if let Some(cell) = st.sheet.cells.get_mut(pos) {
                     cell.value = Value::from(s);
+                } else {
+                    st.sheet.cells.set(pos, Cell { value: Value::from(s), formula: None, style });
                 }
             }
         }
@@ -620,6 +655,16 @@ fn sheet_record(rec: &Record<'_>, st: &mut SheetState<'_>, budget: &mut Budget,
                 st.arrays.insert(at, (range, f));
             }
         }
+        0x000D => {
+            st.calc.mode = match c.u16()? as i16 {
+                0 => CalcMode::Manual,
+                -1 => CalcMode::AutomaticExceptTables,
+                _ => CalcMode::Automatic,
+            }
+        }
+        0x000C => st.calc.set_max_iterations(u32::from(c.u16()?)),
+        0x0011 => st.calc.iterative = c.u16()? == 1,
+        0x0010 => st.calc.set_max_change(c.f64()?),
         0x0236 => report.warn("What-if data tables are not supported; their values were kept."),
         0x00E5 => {
             let n = usize::from(c.u16()?);
@@ -736,7 +781,7 @@ fn formula_cell(c: &mut Cursor<'_, '_>, st: &mut SheetState<'_>, budget: &mut Bu
     st.sheet.cells.set(pos, Cell { value, formula: None, style });
     st.last_formula = Some(pos);
     if string_result {
-        st.pending_string = Some(pos);
+        st.pending_string = Some((pos, style));
     }
     // PtgExp: part of a shared or array formula anchored at another cell.
     if f.rgce.len() == 5 && f.rgce.first() == Some(&0x01) {
diff --git a/docs/cli.md b/docs/cli.md
index b3ee318..7964b76 100644
--- a/docs/cli.md
+++ b/docs/cli.md
@@ -78,6 +78,11 @@ exactly. Skipped, and counted separately:
 - *volatile*: `RAND`, `RANDARRAY`, `RANDBETWEEN`, `NOW`, `TODAY`, `INFO`, `CELL("filename")`, names that use them, and
   every formula that reads such a cell (through the dependency graph).
 
+A logical result the producer cached as the number 1 or 0, without `t="b"` (Business Central's "Open in Excel"
+exports write `<c><f>TRUE()</f><v>1</v></c>`), holds the same value: it matches GridCraft's TRUE or FALSE and is also
+counted as *booleans saved as 1/0* (`boolAsNumber`). Excel types logical results, so on files it saved this count
+should be 0; a non-zero count there would point at a formula where GridCraft returns a logical and Excel a number.
+
 Each mismatch lists the cell, formula, expected (cached) and actual (GridCraft) values and the functions the formula
 calls. Mismatches roll up by function: *checked* (formula cells calling it), *mismatched*, and *primary* (mismatched
 while none of the cell's precedents mismatch — the likely culprit, as opposed to a downstream effect). They also roll
@@ -86,9 +91,10 @@ up by *signature*, `expected type → actual type` (e.g. `number → #SPILL!`),
 **Round trip.** The recalculated workbook is written with GridCraft's XLSX writer, the package is validated (every
 part has a content type, every content-type override and internal relationship target exists, relationship ids are
 unique: what Excel would "repair") and read back. Categories compared: `package`, `sheets` (names and order),
-`values`, `formulas`, `numFmts` (per cell), `merges`, `names`, `tables` (name, range, columns), `condFormats` (rules
-per sheet), `validations`, `charts` (kinds and series counts), `comments`, `hyperlinks`, `pivots`. `#SPILL!`/`#CALC!`
-compare equal to `#VALUE!` and `#CIRC!` to 0, as that's what the file format stores.
+`values`, `formulas`, `numFmts` (per cell), `merges`, `names`, `tables` (name, range, columns), `condFormats` (each
+sheet's rules in priority order, priority numbers aside), `validations`, `charts` (kinds and series counts), `comments`,
+`hyperlinks`, `pivots`. `#SPILL!`/`#CALC!` compare equal to `#VALUE!` and `#CIRC!` to 0, as
+that's what the file format stores.
 
 Files that fail to open are reported with GridCraft's error and don't stop the run. Exit code: 0 when every file
 opened with no mismatch and no round-trip difference, 1 otherwise, 2 on a usage error. `--max-report` caps the
@@ -110,6 +116,7 @@ added, a changed meaning bumps the version):
     "calc": {
       "formulaCells": 3, "checked": 2, "matched": 1, "mismatched": 1, "noOracle": 1, "volatile": 0,
       "staleCache": false,             // fullCalcOnLoad: nothing compared
+      "boolAsNumber": 0,               // matched TRUE/FALSE results the producer saved as 1/0 (no t="b")
       "mismatches": [{"cell": "Sheet1!B1", "formula": "=SUM(A1:A2)", "expected": 7, "actual": 6,
                       "kind": "numeric",  // numeric | text | bool | error | blank (GridCraft empty) | type
                       "functions": ["SUM"], "primary": true}],
@@ -123,7 +130,7 @@ added, a changed meaning bumps the version):
     }
   }],
   "totals": {"files": 1, "opened": 1, "failedToOpen": 0, "formulaCells": 3, "checked": 2, "matched": 1,
-             "mismatched": 1, "noOracle": 1, "volatile": 0, "roundTripFailed": 0, "roundTripDiffering": 1,
+             "mismatched": 1, "noOracle": 1, "volatile": 0, "boolAsNumber": 0, "roundTripFailed": 0, "roundTripDiffering": 1,
              "categoriesDiffering": {"values": 1}},
   "functions": [{"name": "SUM", "checked": 1, "mismatched": 1, "primary": 1}],  // all files, most mismatched first
   "signatures": {"number → number": 1}
diff --git a/docs/file-format-parity.md b/docs/file-format-parity.md
index 5cf441c..0436d96 100644
--- a/docs/file-format-parity.md
+++ b/docs/file-format-parity.md
@@ -1,6 +1,10 @@
 # File-format parity
 
 > **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** trivial (CSV and TSV export is capped at 512 MiB and refuses a larger used range with an error (#528); previously minor: CSV save keeps the separator it was opened with) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (`.xls` import reads the calculation settings) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (editable ink round-trips as DrawingML geometry) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (`.xls` array formulas fill their range on recalculation) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (macOS Open With offers GridCraft for `.xlsb` and `.ods`) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
 
 Every format Excel opens or saves, with GridCraft's read and write support, fidelity and tests.
 Part of [target-app-parity.md](target-app-parity.md). **File formats: ~50% ready, 80–120 h**
@@ -13,6 +17,13 @@ support comes from `crates/engine/src/io.rs` (`FileKind`), `crates/xlsx/src` and
 
 ## Workbook formats
 
+Ink created with Draw is written as standard, unfilled DrawingML polylines, without visible point
+captions or private metadata. Supported numeric polylines reopen as editable ink, retaining points,
+colour, integer width and anchor. Curves, filled paths, transforms and unsupported line styles are
+not interpreted as ink. This does not implement Office InkML or fix inserted icons (#551).
+Command and package tests cover repeated saves and unrelated cell edits; external Excel rendering
+and repair-free opening remain unverified.
+
 | Format | Excel | GridCraft read | GridCraft write | Fidelity / notes | Tests |
 |---|---|---|---|---|---|
 | `.xlsx` Excel Workbook (transitional) | R/W, native | yes | yes | Cells, shared/array/dynamic formulas, styles, themes, merges, CF, validation, tables, comments and notes, hyperlinks, names, freeze panes, outline, print settings, pictures, shapes, charts (simplified, see [chart-parity.md](chart-parity.md)), sparklines, PivotTables (caches and tables), protection, calc settings. **Kept unchanged on save (pass-through, `passthrough.rs`):** custom document properties, ribbon customisation and add-in task panes, custom XML, links to external workbooks (never followed or refreshed), data connections, sheet query tables, printer settings (#324), form controls, ActiveX controls, OLE objects and sheet backgrounds (with their VML shapes); dropped when their sheet is deleted or their parts point at content GridCraft rewrites. **Not preserved:** slicers and slicer caches, timelines, data model, query tables attached to tables, sheet and workbook `extLst` entries we don't model, chart details; Strict Open XML files keep nothing. Never checked in Excel across a corpus: repair prompts unknown. 100 MB files fail (#175) | `roundtrip.rs`, `fixtures.rs`, `malformed.rs`, `pivot_tests.rs` |
@@ -22,7 +33,7 @@ support comes from `crates/engine/src/io.rs` (`FileKind`), `crates/xlsx/src` and
 | `.xlsm` Macro-Enabled Workbook | R/W | yes | yes, macros kept, not run | The VBA project is kept byte-for-byte and written back only into `.xlsm`/`.xltm` (#6); macros never run. Saved with the macro-enabled workbook content type | `roundtrip.rs` (`vba_project_roundtrip`, `package_kind_sets_workbook_content_type`), engine `io.rs` (`macros_are_saved_only_into_xlsm`) |
 | `.xltx` / `.xltm` templates | R/W | yes | partial | Saved with the template (and macro-enabled template) content type, chosen by extension; `.xltm` keeps a VBA project, `.xltx` drops it; "new from template" behaviour missing | `roundtrip.rs` (`package_kind_sets_workbook_content_type`), engine `io.rs` |
 | `.xlsb` Binary Workbook | R/W | **values only** (#101) | no | Names, visibility, numbers, text, booleans, errors, merges, cached formula results; no formulas, formatting, charts, names | `xlsb_tests.rs` |
-| `.xls` Excel 97-2003 (BIFF8) | R/W | **yes, partial** (#121) | no (Save As `.xlsx`) | Clean-room from [MS-CFB] and [MS-XLS]. Read: worksheets and visibility, shared strings, numbers, text, booleans, errors, formulas (text for the common tokens, shared and array formulas, 3-D refs, names, newer functions called by name) with cached results, number formats (dates display as dates), 1904 date system, merges, column widths, row heights, defined names, print area and titles. Not read: fonts, fills, borders, alignment, charts, pictures, comments, CF, validation, hyperlinks, freeze panes, external links (formula kept as its value). Chart and macro sheets skipped with a warning; encrypted (FILEPASS) and BIFF5 (Excel 5.0/95) files refused with a message. Opens as a new unsaved workbook. Unverified on a real-world corpus | `xls_tests.rs` |
+| `.xls` Excel 97-2003 (BIFF8) | R/W | **yes, partial** (#121) | no (Save As `.xlsx`) | Clean-room from [MS-CFB] and [MS-XLS]. Read: worksheets and visibility, shared strings, numbers, text, booleans, errors, formulas (text for the common tokens, shared and array formulas, 3-D refs, names, newer functions called by name) with cached results, number formats (dates display as dates), 1904 date system, merges, column widths, row heights, defined names, print area and titles, calculation settings (mode, iteration with its maximum iterations and change, precision as displayed). Not read: fonts, fills, borders, alignment, charts, pictures, comments, CF, validation, hyperlinks, freeze panes, external links (formula kept as its value). Chart and macro sheets skipped with a warning; encrypted (FILEPASS) and BIFF5 (Excel 5.0/95) files refused with a message. Opens as a new unsaved workbook. Unverified on a real-world corpus | `xls_tests.rs` |
 | `.xlt` Excel 97-2003 template | R/W | yes (read as `.xls`) | no | | — |
 | `.xlam` / `.xla` add-ins | R/W | no | no | VBA; out of scope | — |
 | `.xml` XML Spreadsheet 2003 | R/W | no | no | Simple to support | — |
@@ -40,7 +51,7 @@ support comes from `crates/engine/src/io.rs` (`FileKind`), `crates/xlsx/src` and
 | `.txt` tab-delimited, Unicode text | R/W | yes (`.txt`, `.tsv`, `.tab`) | yes (displayed values) | Text Import Wizard options partly via Text to Columns |
 | `.prn` formatted text (space-delimited) | R/W | no | no | |
 | `.dif`, `.slk` (SYLK) | R/W | no | no | Small, legacy |
-| `.htm` / `.html` web page | R/W (Windows) | yes, via Get Data ▸ From HTML | yes (one sheet as a table) | Formatting not exported |
+| `.htm` / `.html` web page | R/W (Windows) | yes, via Get Data ▸ From HTML | yes (one sheet as a table; a used range taller than 100,001 rows fails with an error instead of being cut short) | Formatting not exported |
 | `.mht` / `.mhtml` single-file web page | R/W (Windows) | no | no | |
 | `.json` | via Power Query | GridCraft's own workbook JSON (debug) and JSON import | GridCraft JSON | Not Power Query's JSON shaping; notes and hyperlinks break export (#126) |
 | `.xml` with XML maps | Developer ▸ Import/Export | no | no | |
@@ -79,6 +90,10 @@ refresh. Counted under features (Get & Transform, ~10% ready), not here.
 | Date | Change | Summary |
 |---|---|---|
 | 2026-10-12 | trivial | CSV and TSV export is capped at 512 MiB and refuses a larger used range with an error (#528) |
+| 2026-10-12 | minor | `.xls` import reads the calculation settings (CalcMode, CalcIter, CalcCount, CalcDelta, CalcPrecision), so circular models calculate instead of showing `#CIRC!` (#724) |
+| 2026-10-12 | minor | Ink paths and editing survive XLSX save/reopen; strict polyline import and malformed-input controls |
+| 2026-10-12 | minor | `.xls` import: the other cells of an array formula ({=FREQUENCY(...)}, {=TREND(...)}) drop their cached results, as `.xlsx` import does, so the formula fills its range on recalculation instead of showing `#SPILL!` against its own old values; 79 fewer mismatching formulas and 16 fewer round-trip differences over 4,224 real-world files |
+| 2026-10-12 | minor | macOS: the app bundle declares `.xlsb` and `.ods`, so Finder's Open With offers GridCraft for them, as Linux and Windows already did (#321) |
 | 2026-10-12 | minor | CSV: saving a file opened as CSV keeps its detected separator (`;` files were rewritten with `,`) |
 | 2026-10-11 | minor | XLSX: cell/shared/array formulas read through the file→model conversion (`_xlpm.` LET/LAMBDA parameter prefixes stripped); table column names keep line breaks; table names may start with `\` |
 | 2026-10-11 | minor | CSV/TSV export writes displayed values (number formats applied, no `#####`); `.xltx`, `.xltm` and `.xlsm` saved with their own workbook content types |
diff --git a/docs/gaps.md b/docs/gaps.md
index 17a56b8..540d17a 100644
--- a/docs/gaps.md
+++ b/docs/gaps.md
@@ -1,6 +1,7 @@
 # Gaps
 
-> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (direct desktop printing through craft-print) · **Target:** Microsoft Excel (Microsoft 365)
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (ink XLSX preservation; icons still pending) · **Target:** Microsoft Excel (Microsoft 365)
+> **Last reviewed:** 2026-10-12 · **Last updated:** 2026-10-12 · **Change:** minor (§8: PivotTable values on rows) · **Target:** Microsoft Excel (Microsoft 365)
 
 Every known shortfall against Excel, one entry each, ranked by user impact (what blocks someone
 using GridCraft for real work first). This is the work list: pick from the top, check the open
@@ -79,7 +80,8 @@ No alpha blockers: every core workflow passes the [alpha gate](roadmap.md#alpha-
 
 ### 8. PivotTables: no slicers, calculated items, PivotCharts; unverified in Excel (F)
 - **Evidence:** `parity-checklist.md` missing `insert.slicer`, `insert.timeline`,
-  `insert.pivotChart`, `table.insertSlicer`; calculated items and GETPIVOTDATA missing (calculated fields done).
+  `insert.pivotChart`, `table.insertSlicer`; calculated items and GETPIVOTDATA missing (calculated fields
+  and values on rows done).
 - **Impact:** pivots are the analyst's main tool.
 - **Estimate:** 20–30 h for beta (25–40 h full).
 
@@ -106,12 +108,17 @@ No alpha blockers: every core workflow passes the [alpha gate](roadmap.md#alpha-
 
 ### 13. Analysis tools: Solver, Analysis ToolPak, Forecast Sheet (F)
 - `data.solver`, `data.analysisToolPak` missing. Forecast Sheet (`data.forecastSheet`) and the
-  FORECAST.ETS family are in; the sheet has no Forecast Start (hindcast) option yet. **Estimate:** 15–25 h.
+  FORECAST.ETS family are in, including Forecast Start (hindcast, #785). **Estimate:** 15–25 h.
+- Solver (`data.solver`, #327) has Simplex LP with integer/binary branch and bound, a local
+  nonlinear method (augmented Lagrangian, not GRG), the Evolutionary method, and Answer and
+  Limits reports; AllDifferent constraints, the Solver Options dialog, the Sensitivity and
+  Population reports and Load/Save Model remain. The Analysis ToolPak
+  (`data.analysisToolPak`) has 13 of 19 tools. Forecast Sheet (`data.forecastSheet`) and the
+  FORECAST.ETS family are in; the sheet has no Forecast Start (hindcast) option yet. **Estimate:** 12–20 h.
 
 ### 14. Page Layout view and print polish (U, F)
 - Page Layout view landed (#329): paper view with rulers and in-place header/footer editing.
-  Remaining: pictures in headers/footers, Different First Page / Odd & Even pages, dragging
-  margins on the ruler. Desktop now submits directly through craft-print with printer choice, copies, duplex and grayscale; browser printing stays available. Print ranges and driver tray/options UI remain. **Estimate:** 5–10 h.
+  Margins are dragged on the rulers (#792). Remaining: pictures in headers/footers, Different First Page / Odd & Even pages. Desktop now submits directly through craft-print with printer choice, copies, duplex and grayscale; browser printing stays available. Print ranges and driver tray/options UI remain. **Estimate:** 5–10 h.
 
 ### 15. Remaining functions and an oracle suite (F)
 - 18 missing, 9 stubs; no Excel-computed oracle corpus; #137, #138. **Estimate:** 16–26 h.
@@ -125,6 +132,8 @@ No alpha blockers: every core workflow passes the [alpha gate](roadmap.md#alpha-
   conversion; cloud storage requested (#86). **Estimate:** 35–55 h (co-authoring scope needs the owner).
 
 ### 17. Insert objects (F)
+- Ink strokes now survive XLSX save/reopen as editable polylines. Inserted icons still lose their
+  identity/artwork on save (#551); native Office InkML import is not implemented.
 - SmartArt, WordArt, equations, signature line, objects, 3-D models, screenshot; 8 shape kinds vs
   ~170; pictures in cells (#61, PR #105). **Estimate:** 25–40 h.
 
@@ -160,6 +169,10 @@ No alpha blockers: every core workflow passes the [alpha gate](roadmap.md#alpha-
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-12 | minor | Page Layout view: dragging margins on the rulers (#792) removed from the §14 remainder |
+| 2026-10-12 | minor | §13: Forecast Sheet Forecast Start (hindcast) landed (#785) |
+| 2026-10-12 | minor | §17: ink geometry survives XLSX saves; the icon portion of #551 remains |
+| 2026-10-12 | minor | §8: values on rows (Σ Values in Rows, `dataOnRows`) laid out, moved and round-tripped |
 | 2026-10-12 | minor | Desktop File > Print now discovers printers and submits PDF jobs through pinned craft-print with printer choice, copies, duplex and grayscale; browser printing and PDF export remain available. Remaining print parity includes page ranges and driver-specific tray/options UI; physical printer fidelity needs hardware validation. |
 | 2026-10-11 | minor | §6: iterative calculation for circular references landed (Maximum Iterations, Maximum Change) |
 | 2026-10-11 | minor | §15: trim-reference operators (`A1:.E10`, `A1.:E10`, `A1.:.E10`) parse and evaluate |
diff --git a/docs/localization-parity.md b/docs/localization-parity.md
index e7d1de9..bbcead7 100644
--- a/docs/localization-parity.md
+++ b/docs/localization-parity.md
@@ -1,6 +1,7 @@
 # Localization parity
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-11 · **Change:** minor (German ribbon catalog added) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-12 · **Change:** minor (Format Cells dialog looks its labels up in the catalog) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-12 · **Change:** minor (Brazilian Portuguese catalog: dialogs, menus and tooltips) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
 
 Per-language status against Excel, which ships its UI in dozens of languages (Windows language
 packs cover 100+), with localized function names, argument separators, number and date formats,
@@ -14,7 +15,8 @@ right-to-left sheets and full complex-script support. Part of
   system language (closes #20) and a View-tab switcher, with English-keyed lookup tables:
   Japanese 268 labels, Simplified Chinese, Korean, Russian, Brazilian Portuguese, German and Czech 266
   each. The tables are used by
-  the ribbon, sheet tabs and widgets (`ribbon.rs`, `tabs.rs`, `widgets.rs`); dialogs, menus,
+  the ribbon, sheet tabs and widgets (`ribbon.rs`, `tabs.rs`, `widgets.rs`), the Format Cells
+  dialog, every dialog title and the shared OK/Cancel buttons; the other dialogs, menus,
   context menus, task panes, status messages, command labels and function descriptions are still
   English literals. Untranslated labels fall back to English.
 - **About 2,200 user-visible strings** in all (heuristic source scan: ~1,700 UI and command
@@ -48,7 +50,7 @@ separators, number/date formats, machine translation with agent review, and scri
 | Hindi | hi | 0 (0%) | no | Devanagari: **no shaping** | no | none | 12–18 h |
 | Arabic | ar | 0 (0%) | no | **no shaping, no RTL UI**; Sheet Right-to-Left mirrors the grid (#146) | no | none | 25–35 h |
 | French | fr | 0 (0%) | no | Latin: yes | no | none | 6–10 h |
-| Portuguese | pt-BR | 266 (~12%) | no | Latin: yes | no | menus only | 4–8 h |
+| Portuguese | pt-BR | 923 (~42%) | dialogs and tooltips (dialogs take effect with #669) | Latin: yes | no | menus, File view, dialogs | 2–4 h |
 | Indonesian | id | 0 (0%) | no | Latin: yes | no | none | 5–8 h |
 | Japanese | ja | 268 (~12%) | no | CJK system-font fallback; IME unverified; no furigana display | no | menus only | 8–12 h |
 | German | de | 266 (~12%) | no | Latin: yes | no | menus only | 4–8 h |
@@ -77,6 +79,8 @@ language (none so far) and of localized function names.
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-12 | minor | Format Cells looks up its tabs, labels, options and note through `Language::tr` (Fill tab keyed `Format Cells\|Fill`); dialog titles and OK/Cancel too. Labels already in a table (Number, Currency, Fill…) show translated; the rest fall back to English until the tables add them |
+| 2026-10-12 | minor | Brazilian Portuguese catalog (`i18n/pt.rs`) grows from 377 to 923 entries: every key the other catalogs translate, including the dialog strings #669 starts looking up (~42%) |
 | 2026-10-11 | minor | German ribbon catalog (`i18n/de.rs`, 266 labels, ~12%); `de` locale tags (de-DE, de-AT, de-CH…) resolve to German. PR #163 (localized German formulas/numbers) still open |
 | 2026-10-11 | minor | Sheet Right-to-Left mirrors the grid (#146) |
 | 2026-10-11 | minor | Czech (cs) ribbon table: 266 labels (~12%), menus only |
diff --git a/docs/releasing.md b/docs/releasing.md
index 7f7ecce..479c2c0 100644
--- a/docs/releasing.md
+++ b/docs/releasing.md
@@ -15,7 +15,7 @@ This is GridCraft's implementation of the shared [release playbook](release-play
 | Display name `GridCraft`, binaries `gridcraft` + `gridcraft-cli` | every script and workflow |
 | Bundle / app id `ai.storyteller.gridcraft` | `packaging/macos/Info.plist.in`, `packaging/linux/*`, flatpak manifest |
 | WiX UpgradeCode `5511327B-F305-41BE-92D0-EB84944E7C4D` (fixed forever) | `packaging/windows/gridcraft.wxs` |
-| File types `.xlsx` `.xlsm` `.csv` `.tsv` | Info.plist (`CFBundleDocumentTypes`), WiX (ProgIds/OpenWithProgids), `.desktop` `MimeType=`, `ai.storyteller.gridcraft.mime.xml`, metainfo |
+| File types `.xlsx` `.xlsm` `.xlsb` `.ods` `.csv` `.tsv` | Info.plist (`CFBundleDocumentTypes`), WiX (ProgIds/OpenWithProgids), `.desktop` `MimeType=`, `ai.storyteller.gridcraft.mime.xml`, metainfo |
 | Web app dir `apps/gridcraft-web` | `packaging/web/package.sh` |
 | App colour `#1f9d55` (ink `#147a40`), **proposed** | `assets/app-icon/README.md`, metainfo `<branding>` |
 
@@ -94,9 +94,9 @@ and upload their artifacts, the environment refuses macOS and Windows, and no re
 
 - `Info.plist` comes from `Info.plist.in`: bundle id `ai.storyteller.gridcraft`,
   `LSMinimumSystemVersion` 11.0, `NSHighResolutionCapable`, category productivity, and
-  `CFBundleDocumentTypes` for `.xlsx`, `.xlsm`, `.csv` and `.tsv` with rank **Alternate**, so
-  GridCraft is offered in *Open With* without taking over Numbers' (or another app's)
-  defaults. `.xlsm` gets an imported UTI in case macOS doesn't know it.
+  `CFBundleDocumentTypes` for `.xlsx`, `.xlsm`, `.xlsb`, `.ods`, `.csv` and `.tsv` with rank
+  **Alternate**, so GridCraft is offered in *Open With* without taking over Numbers' (or another
+  app's) defaults. `.xlsm` and `.xlsb` get imported UTIs in case macOS doesn't know them.
 - **Signing** goes inside-out with the hardened runtime and a secure timestamp; no `--deep` on
   the final signature; `entitlements.plist` is deliberately empty.
 - **Notarization:** the app is zipped and sent with `xcrun notarytool submit --wait`, then
diff --git a/docs/target-app-parity.md b/docs/target-app-parity.md
index 8b82092..5b4fa6d 100644
--- a/docs/target-app-parity.md
+++ b/docs/target-app-parity.md
@@ -1,6 +1,7 @@
 # Target-app parity: GridCraft vs Microsoft Excel
 
-> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-11 · **Change:** minor (stability: command-sequence fuzzing against undo/redo, XLSX round-trip and full-recalc invariants) · **Target:** Microsoft Excel (Microsoft 365)
+> **Last reviewed:** 2026-10-11 · **Last updated:** 2026-10-12 · **Change:** minor (sheet-tab navigation reveals the selected tab without interrupting manual scrolling) · **Target:** Microsoft Excel (Microsoft 365)
+> **Last reviewed:** 2026-10-12 · **Last updated:** 2026-10-12 · **Change:** minor (PivotTables: values on rows) · **Target:** Microsoft Excel (Microsoft 365)
 
 This is the authoritative parity assessment. [`ROADMAP.md`](../ROADMAP.md) summarizes it,
 [`gaps.md`](gaps.md) lists every shortfall, and the area checklists hold the detail:
@@ -84,10 +85,10 @@ performance 8, stability 8, localization 4, hardware 2, platforms 2, ecosystem 2
 | Editing, navigation, clipboard, fill | 12 | ~90% | ~70% | 15–25 | Point mode, F4, AutoComplete, Paste Special, AutoFill, Flash Fill, Find/Replace, Go To Special. Bugs: rectangular drag-select (#28), monthly fill (#132), cut across sheets (#128), Insert Copied Cells missing (#21), key tips only on part of the Home tab (#43; #33, #49). [ui-parity.md](ui-parity.md) |
 | Cell formatting, styles, conditional formatting | 10 | ~95% | ~80% | 8–14 | Full number-format language, borders, 47 cell styles, 60 table styles, all CF rule kinds including data bars, colour scales and icon sets. Gaps: font weights beyond regular/bold (#168), system fonts list (#4), themes |
 | Sort, filter, tables, validation, outline | 8 | ~82% | ~70% | 10–16 | Multi-level sort, AutoFilter, Advanced Filter, tables with totals, validation, outline, subtotals, consolidate. Bugs: subtotal header (#131), validation edits (#129), table style panic caught (#130); no slicers on tables |
-| PivotTables | 7 | ~65% | ~45% | 25–40 | Insert/Recommended, field list, three layouts, date grouping, show-values-as, refresh, calculated fields, XLSX round-trip. Missing: slicers, timelines, calculated items, PivotCharts, value/label filters, number grouping, GETPIVOTDATA, data-model pivots. Round-trip never checked in Excel |
+| PivotTables | 7 | ~65% | ~45% | 25–40 | Insert/Recommended, field list, three layouts, values on rows or columns, date grouping, show-values-as, refresh, calculated fields, XLSX round-trip. Missing: slicers, timelines, calculated items, PivotCharts, value/label filters, number grouping, GETPIVOTDATA, data-model pivots. Round-trip never checked in Excel |
 | Charts and sparklines | 8 | ~50% | ~30% | 40–60 | 25 chart kinds, all 2-D. The chart model holds title, legend position, a data-labels flag, gridlines flag and axis titles; no axis scaling, trendlines, error bars, per-point formatting, chart sheets, 3-D, surface, map, Pareto. Several kinds don't survive XLSX round trip (open PRs #158, #161). [chart-parity.md](chart-parity.md) |
 | Page layout, print, PDF | 5 | ~80% | ~55% | 12–20 | Page setup, print titles, breaks, Page Break Preview, headers/footers, PDF export and printing. No true Page Layout view; the PDF writer uses only the 14 standard fonts without embedding (no CJK or other non-Latin text in PDF); web print only exports (#141, #143) |
-| What-if and analysis | 4 | ~50% | ~40% | 22–35 | Goal Seek, Scenario Manager, data tables, Analysis ToolPak (13 of 19 tools, no charts). Missing: Solver, Forecast Sheet, Analyze Data |
+| What-if and analysis | 4 | ~50% | ~40% | 22–35 | Goal Seek, Scenario Manager, data tables, Analysis ToolPak (13 of 19 tools, no charts), Solver (Simplex LP, a local nonlinear method and Evolutionary; Answer and Limits reports; no Sensitivity report or options dialog). Missing: Forecast Sheet, Analyze Data |
 | Get & Transform, external data, data model | 5 | ~15% | ~10% | 60–100 | Import of CSV/TSV, JSON, HTML. No Power Query editor, no From Web, database or folder sources, no connections or refresh, no relationships or data model, no external workbook links (dropped with a warning) |
 | Insert objects | 3 | ~55% | ~45% | 25–40 | Pictures, 8 shape kinds (Excel has ~170), text boxes, own icon set, ink with Ink to Shape, hyperlinks, checkboxes. Missing: SmartArt, WordArt, equations, signature line, objects, 3-D models, screenshot, pictures in cells (PR #105) |
 | Review, comments, protection, collaboration | 4 | ~55% | ~40% | 35–55 | Threaded comments, notes, spelling (system dictionary), thesaurus, sheet and workbook protection, Allow Edit Ranges with Excel-compatible password hashes (#307). Missing: comment navigation, Show Changes, notes-to-comments conversion, accessibility checker, co-authoring, opening password-encrypted files (refused with a message since #17) |
@@ -301,7 +302,7 @@ The inventory carried over from the 2026-10-07 ROADMAP.md, updated for what land
   average, colour), tables with totals rows, remove duplicates, text to columns, data validation
   with error alerts, grouping/outline, subtotals.
 - PivotTables: Insert/Recommended PivotTables, field list pane, compact/outline/tabular layouts,
-  date grouping, sort, filters, show-values-as, refresh, and XLSX round-trip.
+  values on rows or columns, date grouping, sort, filters, show-values-as, refresh, and XLSX round-trip.
 - Page layout & print: Page Break Preview, print settings, PDF export and printing.
 - What-if: Goal Seek, scenarios, data tables. Spelling (system word list) and thesaurus.
 - Draw: pen, highlighter, eraser, ink strokes and Ink to Shape. Task panes: Comments (threaded
@@ -332,6 +333,8 @@ The inventory carried over from the 2026-10-07 ROADMAP.md, updated for what land
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-12 | minor | Sheet tabs: reveal the selected tab on navigation and resize while preserving manual scrolling (#681); no score change |
+| 2026-10-12 | minor | PivotTables: values on rows (Σ Values in Rows at any position, all three layouts; `pivot.moveField` and the field pane move it; `dataOnRows` round-trips) (no score change) |
 | 2026-10-11 | minor | Stability: command-sequence fuzz harness (`crates/engine/tests/command_sequence_fuzz.rs`) checks random command sequences against undo/redo, XLSX round-trip, full-recalc and structure invariants; the sequence bugs it found are fixed (no score change) |
 | 2026-10-11 | minor | Password-encrypted workbooks open (#11): Essentials file-opening work 24–36 h |
 | 2026-10-11 | minor | Worksheet functions 505 / 523 (96.6%; 496 working): ODDFPRICE, ODDFYIELD, ODDLPRICE, ODDLYIELD |
diff --git a/docs/ui-parity.md b/docs/ui-parity.md
index 10abcbc..7e308cb 100644
--- a/docs/ui-parity.md
+++ b/docs/ui-parity.md
@@ -1,6 +1,8 @@
 # UI parity
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-11 · **Change:** minor (AutoFit reserves filter dropdown space, observed against Windows Excel) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-12 · **Change:** minor (sheet-tab navigation reveals the selected tab without interrupting manual scrolling) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-12 · **Last updated:** 2026-10-12 · **Change:** minor (Alt+Down opens AutoFilter header menus) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-12 · **Change:** minor (ribbon and menu Paste paste the system clipboard like Cmd/Ctrl+V; regression test for the Paste button freeze, #273; Paste button gets an accessible name) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4
 
 Interaction, controls and feel, against Excel. Part of [target-app-parity.md](target-app-parity.md).
 **UI/UX fidelity: ~55% ready, 50–80 h** (estimated). Ribbon command coverage is measured
@@ -21,14 +23,14 @@ Sources: `crates/ui-egui/src` (ribbon, grid, editor, formula bar, dialogs, panes
 | Ribbon collapse, simplified ribbon, customize ribbon/QAT | yes | partial | customization missing |
 | Key tips (Alt / F10 then letters) | yes, every ribbon control | **initial** (#43, 10-10): Alt or F10 shows key tips on Home for alignment, Paste Special and AutoFit plus legacy Alt sequences; other tabs and controls not yet (#33, #49) | 3–5 h |
 | Formula bar with Name Box, expand, function hints | yes | yes | done |
-| Sheet tabs: rename, reorder, colour, hide, scroll | yes | yes | rename focus bug on macOS (#145) |
+| Sheet tabs: rename, reorder, colour, hide, scroll | yes | yes | active tab revealed on navigation and resize (#681); manual wheel/trackpad browsing preserved; rename focus bug on macOS (#145) |
 | Status bar: Sum/Count/Average and more, view buttons, zoom | yes | yes | customizable statistics partial |
 | Task panes (Format Chart, Comments, Watch, Selection, PivotTable fields) | yes | yes | element-level Format pane for shapes and pictures missing |
 | Backstage (File) view: Info, New with templates, Open recent, Export, Options | yes | partial | Options dialog and template gallery missing |
 | Dark mode, system appearance | yes | yes | done (10-09); follows the system on first run, title-bar switch and File › Display theme (#194, #239) |
 | Backstage (File) view: Info, New with templates, Open recent, Export, Options | yes | yes (#174, 10-11): the File tab opens a full-window view (Esc or the back arrow return) with Home, New (blank + the three samples), Open (recent + Browse), Info (location, properties, Protect Workbook), Save, Save As, Print (page preview, active sheet or workbook, fit to page, Page Setup), Export (PDF, CSV, web page), Close and Options (`file.options`: theme, language, formula bar, AutoSave, calculation) | no Account, Share or template gallery beyond the samples; Options applies at once (no OK/Cancel dialog) and holds only the settings GridCraft has |
 | Dark mode, system appearance | yes | yes | done (10-09) |
-| Page Layout view (paper view with rulers and header editing) | yes | yes (#329, 10-11): per-sheet view saved in XLSX, pages with margins and gaps on the print pagination, "Click to add data" pages, rulers (inches or centimetres), headers and footers drawn and edited in place with a Header & Footer tab | header/footer pictures, Different First Page / Odd & Even, ruler margin dragging missing (1–3 h) |
+| Page Layout view (paper view with rulers and header editing) | yes | yes (#329, 10-11): per-sheet view saved in XLSX, pages with margins and gaps on the print pagination, "Click to add data" pages, rulers (inches or centimetres), headers and footers drawn and edited in place with a Header & Footer tab | margins drag on the rulers (#792, with header and footer margins); header/footer pictures, Different First Page / Odd & Even missing (1–3 h) |
 | Multiple windows per workbook | yes | no (#162) | see [hardware-parity.md](hardware-parity.md) |
 
 ## Grid interaction
@@ -117,6 +119,7 @@ otherwise. Number-format and border keys match the physical key (Ctrl+Shift+4, w
 | Ctrl+Alt+V | Cmd+Control+V, Cmd+Option+V | Paste Special | **added** |
 | Ctrl+Alt+= / Ctrl+Alt+- | — | zoom in / out (10% steps) | **added** |
 | Alt+=, Alt+Down, Alt+Page Down / Up | Option+Down, Option+Page Down / Up | AutoSum, drop-down list, one screen right / left | **added** |
+| Alt+Down on a filter header | Option+Down | Open the existing AutoFilter popup; validation dropdowns keep priority | **added** (AutoFilter portion of #441; Ribbon dropdowns and column value picker are separate work) |
 | Alt+F1, Alt+Shift+F1, Shift+F11 | Shift+F11 | embedded chart, new sheet | **added** |
 | Shift+F2, Ctrl+Shift+F2 | Shift+F2, Cmd+Shift+F2 | note, threaded comment | **added** |
 | Shift+F3, Ctrl+F3, Ctrl+Shift+F3 | Shift+F3, Cmd+F3 (Define Name), Cmd+Shift+F3 | Insert Function, Name Manager, Create from Selection | **added** |
@@ -160,6 +163,9 @@ scrollbar bugs 2–4 · pixel/feel pass against observed Excel 7–12.
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-12 | minor | Page Layout view: left/right/top/bottom margins are dragged on the rulers (#792) |
+| 2026-10-12 | minor | Alt+Down opens the active filter header's existing popup, with validation priority and mirrored anchoring on right-to-left sheets (part of #441) |
+| 2026-10-12 | minor | Paste from the ribbon (button and options menu), the cell and header context menus and the macOS menu bar's Edit menu pastes what is on the system clipboard, as Cmd/Ctrl+V does, instead of only GridCraft's own copy (the web build, which can't read the clipboard on request, still pastes GridCraft's copy). Copy and Cut by keytip (H,C / H,X) publish to the system clipboard like the ribbon buttons. After a control-channel or MCP copy, which leaves the system clipboard alone, Paste pastes that copy until other text is copied. Once a cut has been pasted, Paste (ribbon, menus or Cmd/Ctrl+V) doesn't paste the cut's clipboard text again over the moved cells (Excel pastes a cut once), and the Paste keytip (H,V,P) pastes the system clipboard like the button. Regression test for the Paste button click freeze in 0.5.0 (#273, fixed by #272); the Paste button gets an accessible "Paste" name for screen readers |
 | 2026-10-11 | minor | AutoFit accounts for table and ordinary filter dropdowns, including low zoom; header text excludes the button area |
 | 2026-10-11 | minor | Outline band for grouped rows and columns, Show / Hide Detail on the Data tab, numpad navigation keys in shortcuts (#373) |
 | 2026-10-11 | minor | Shift+Space / Ctrl+Space no longer start an edit; Control+Space selects the column on Mac (#338) |
diff --git a/omastore.toml b/omastore.toml
new file mode 100644
index 0000000..9b91e60
--- /dev/null
+++ b/omastore.toml
@@ -0,0 +1,11 @@
+kind = "app"
+categories = ["Office"]
+icon = "assets/app-icon/hicolor/256x256/apps/ai.storyteller.gridcraft.png"
+
+[linux.x86_64]
+asset = "gridcraft-{version}-linux-x86_64.tar.gz"
+exec = "gridcraft-{version}-linux-x86_64/bin/gridcraft"
+
+[linux.aarch64]
+asset = "gridcraft-{version}-linux-aarch64.tar.gz"
+exec = "gridcraft-{version}-linux-aarch64/bin/gridcraft"
diff --git a/packaging/macos/Info.plist.in b/packaging/macos/Info.plist.in
index 9379279..4ed6d97 100644
--- a/packaging/macos/Info.plist.in
+++ b/packaging/macos/Info.plist.in
@@ -111,6 +111,39 @@
       <key>CFBundleTypeMIMETypes</key>
       <array><string>text/tab-separated-values</string></array>
     </dict>
+    <!-- .xlsb and .ods are imported (data only) into a new workbook that saves as .xlsx. -->
+    <dict>
+      <key>CFBundleTypeName</key>
+      <string>Excel Binary Workbook</string>
+      <key>CFBundleTypeRole</key>
+      <string>Editor</string>
+      <key>LSHandlerRank</key>
+      <string>Alternate</string>
+      <key>LSItemContentTypes</key>
+      <array>
+        <string>com.microsoft.excel.sheet.binary.macroenabled</string>
+      </array>
+      <key>CFBundleTypeExtensions</key>
+      <array><string>xlsb</string></array>
+      <key>CFBundleTypeMIMETypes</key>
+      <array><string>application/vnd.ms-excel.sheet.binary.macroEnabled.12</string></array>
+    </dict>
+    <dict>
+      <key>CFBundleTypeName</key>
+      <string>OpenDocument Spreadsheet</string>
+      <key>CFBundleTypeRole</key>
+      <string>Editor</string>
+      <key>LSHandlerRank</key>
+      <string>Alternate</string>
+      <key>LSItemContentTypes</key>
+      <array>
+        <string>org.oasis-open.opendocument.spreadsheet</string>
+      </array>
+      <key>CFBundleTypeExtensions</key>
+      <array><string>ods</string></array>
+      <key>CFBundleTypeMIMETypes</key>
+      <array><string>application/vnd.oasis.opendocument.spreadsheet</string></array>
+    </dict>
   </array>
 
   <!-- Types macOS may not know; the system's own declaration wins when it has one. -->
@@ -134,6 +167,24 @@
         <array><string>application/vnd.ms-excel.sheet.macroEnabled.12</string></array>
       </dict>
     </dict>
+    <dict>
+      <key>UTTypeIdentifier</key>
+      <string>com.microsoft.excel.sheet.binary.macroenabled</string>
+      <key>UTTypeDescription</key>
+      <string>Excel Binary Workbook</string>
+      <key>UTTypeConformsTo</key>
+      <array>
+        <string>public.data</string>
+        <string>public.zip-archive</string>
+      </array>
+      <key>UTTypeTagSpecification</key>
+      <dict>
+        <key>public.filename-extension</key>
+        <array><string>xlsb</string></array>
+        <key>public.mime-type</key>
+        <array><string>application/vnd.ms-excel.sheet.binary.macroEnabled.12</string></array>
+      </dict>
+    </dict>
   </array>
 
 </dict>