- Animated WebP (J-82) was being flattened to its first frame: browsers
have no animated WebP encoder, so the modal now sniffs the file header
(4 KB range request), explains the limitation and disables Process
instead of overwriting the file with a single frame.
- APNGs saved as .png took the still-image path and lost their frames;
the header sniff looks for the acTL chunk, routes them to the animation
pipeline (all frames + delays) and switches the UI to the animation
options. The worker double-checks the header too, so no path can
flatten an APNG.
- New dependency-free imageformat module, verified against real files
(J-82 animated, static WebP/PNG, and a generated APNG named .png).
JakeBreath
a152063d76