document.exportPdf {standard: pdfX1a|pdfX3|pdfX4} and the PDF/X presets now
write conforming files instead of being refused:
- every PDF/X file gets a /GTS_PDFX output intent (by default the CMYK
profile in effect, embedded), TrimBox, Trapped, GTS_PDFXVersion (and
GTS_PDFXConformance for X-1a), a title and dates; editing data,
passwords and, in X-1a/X-3, PDF layers are refused
- PDF/X-1a converts every colour and image to a CMYK destination,
untagged, with CMYK spot alternates; X-3 and X-4 tag colours with ICC
profiles
- X-1a and X-3 are written as PDF 1.3 and their transparency is flattened
first (High Resolution preset; images with see-through pixels count,
rasters stay opaque); X-4 keeps transparency, is PDF 1.6 at most and
names the standard in its XMP metadata
- the written file is checked against its standard (soft masks,
transparency groups, opacity, blend modes, RGB in X-1a, fonts not
embedded) and refused rather than mislabelled
- choosing a standard sets the latest compatibility it allows and turns
off what it forbids (engine and Save PDF dialog)
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>