diff --git a/crates/ui-egui/src/guide_layout_ui.rs b/crates/ui-egui/src/guide_layout_ui.rs
index 9117baa8..8d47e628 100644
--- a/crates/ui-egui/src/guide_layout_ui.rs
+++ b/crates/ui-egui/src/guide_layout_ui.rs
@@ -157,6 +157,10 @@ pub fn confirm(app: &mut PhotocraftApp, f: &Map<String, Value>) -> Result<Value,
     let color = rgb(color).ok_or("invalid guide color")?;
     let hex = format!("#{:02x}{:02x}{:02x}", color.r(), color.g(), color.b());
     let result = app.run(COMMAND, params(f))?;
+    // The preview is visible even when guides were hidden. Keep a committed layout visible too.
+    app.ui.view.extras = true;
+    app.ui.view.show.canvas_guides = true;
+    app.ui.extras.guides = true;
     app.session.prefs.edit(|prefs| prefs.guides_grid_and_slices.guide_color = hex);
     let mut remembered = f.clone();
     for key in [MARK, "__command", "__label", "__document", "__previewGuides", "__previewParams", "__previewSource"] {
diff --git a/crates/ui-egui/src/guide_layout_ui/tests.rs b/crates/ui-egui/src/guide_layout_ui/tests.rs
index 6ac36cb1..299b3fb8 100644
--- a/crates/ui-egui/src/guide_layout_ui/tests.rs
+++ b/crates/ui-egui/src/guide_layout_ui/tests.rs
@@ -1,5 +1,56 @@
 use super::*;
 
+#[test]
+fn applying_a_previewed_layout_reveals_hidden_guides() {
+    for hidden in ["extras", "canvas", "guides"] {
+        let mut app = app();
+        match hidden {
+            "extras" => app.ui.view.extras = false,
+            "canvas" => app.ui.view.show.canvas_guides = false,
+            _ => app.ui.extras.guides = false,
+        }
+        let id = open(&mut app);
+        let doc = &app.session.active().unwrap().doc;
+        assert!(preview(&app, doc).is_some(), "the dialog shows a preview despite hidden {hidden}");
+        crate::dialogs::confirm(&mut app, id).unwrap();
+        let doc = &app.session.active().unwrap().doc;
+        assert!(!doc.guides.vertical.is_empty(), "the layout was actually created");
+        assert!(preview(&app, doc).is_none(), "the temporary preview is gone");
+        assert!(app.ui.view.shows(app.ui.view.show.canvas_guides) && app.ui.extras.guides, "applied guides must remain visible when {hidden} was hidden");
+    }
+}
+
+#[test]
+fn cancelling_invalid_and_empty_layouts_keep_guides_hidden() {
+    for action in ["cancel", "invalid", "empty"] {
+        let mut app = app();
+        app.ui.view.extras = false;
+        app.ui.view.show.canvas_guides = false;
+        app.ui.extras.guides = false;
+        let id = open(&mut app);
+        match action {
+            "cancel" => {
+                crate::dialogs::cancel(&mut app, id).unwrap();
+            }
+            "invalid" => {
+                app.ui.dialog_mut(id).unwrap().fields.insert("color".into(), json!("invalid"));
+                assert!(crate::dialogs::confirm(&mut app, id).is_err());
+            }
+            _ => {
+                let f = &mut app.ui.dialog_mut(id).unwrap().fields;
+                for key in ["__columnsEnabled", "__rowsEnabled", "__marginEnabled"] {
+                    f.insert(key.into(), json!(false));
+                }
+                f.insert("clearExisting".into(), json!(true));
+                assert!(crate::dialogs::confirm(&mut app, id).is_err(), "an empty layout is rejected");
+            }
+        }
+        let guides = &app.session.active().unwrap().doc.guides;
+        assert!(guides.vertical.is_empty() && guides.horizontal.is_empty(), "{action}");
+        assert!(!app.ui.view.extras && !app.ui.view.show.canvas_guides && !app.ui.extras.guides, "{action} must not change visibility");
+    }
+}
+
 #[test]
 fn tab_includes_optional_sizes_and_shift_tab_selects_their_text() {
     let mut app = app();