A native save was pretty-printed when the document had at most 2,000
layers and objects and its compact JSON was at most 1 MiB. Pretty
printing puts every coordinate on its own indented line, so traced art
with few paths and many anchors could pass that check and be written at
about five times the size of its compact JSON.
The 1 MiB limit now applies to the pretty-printed document, indented as
the file holds it and in the form the save writes: version 1 anchors,
and placed documents expanded for older versions or Include Linked
Files. Documents whose pretty-printed JSON is over 1 MiB are saved as
compact JSON, even when their compact JSON is under it. The 2,000-object
rule and compressed saves are unchanged. docs/mcp.md describes the rule.
PNG, PDF, EPS, legacy `.ai`, packaged zips and saved `.vectorcraft` files
record the wall-clock time they were made in, so the same commands run twice
gave different bytes although the pixels matched (#2880):
PDF /CreationDate and /ModDate D:20261018155816 vs D:20261018155817
PNG the `Creation Time` tEXt entry
.vectorcraft one byte of the stored date
SVG carries no time, and already repeated
`metadata::output_time` is the time a file records: `SOURCE_DATE_EPOCH` when it
holds a non-negative whole number of seconds, else the clock, as the
reproducible-builds specification defines it. A date a command is given
(`file.new {created}`, a save's `modified`) still wins over the variable, and a
blank, negative or non-numeric value is ignored so that an export is never
refused over the environment.
`metadata::now_unix` keeps the real clock and now has exactly two callers, both
of which must not be pinnable from the environment: the recovery heartbeat, and
the seed PDF encryption draws on.
- Format v3: optional gzip (Preferences > File Handling > Use Compression, or
document.save {compress}); compressed files open by their magic bytes, legacy
ones too.
- Every file write goes to a temporary file renamed over the target (engine
writes and the desktop app's writer), so a failed save keeps the old file.
- Only the images the document uses are written.
- Document keys from newer versions are kept (Document.extra, flattened).
- Assigned colour profiles are a real field (Document.color_profiles),
migrated from unknown.colorProfiles on load.
- document.save {version: 1|2} writes files older versions open; {preview}
embeds a PNG of the first artboard of at most 256 px.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>