compatibility "1.3" writes a %PDF-1.3 file (its XMP metadata says 1.3
too) without transparency: a copy of the document is flattened first
with flattenerPreset (stored with PDF presets; empty is High Resolution)
and the flattener options over it, see-through image pixels counting as
transparency and rasterized areas clipped to their regions so no soft
mask is needed. Page groups are left out and the writer refuses a file
that would still have transparency. PDF/X-1a and PDF/X-3 share this
path (their version is now PDF 1.3; 1.4 is still accepted and written
as 1.3), and with it the preset, the header and metadata code and the
transparency check. Passwords at PDF 1.3 encrypt with 40-bit RC4
(revision 2). The Save PDF dialog lists PDF 1.3 and picks the flattener
preset under Advanced.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
79581c7ff5