System > Appearance gains a Thumbnails surface: format (WebP, JPEG XL,
JPEG), quality and size limit, saved to the server with the settings
revision. JPEG XL is offered only when the server has an encoder, else
the option is disabled with the server's reason (D130); a note says
when this browser cannot show JPEG XL. Saving a new format converts
nothing: the row then says previews keep their old format.
Thumbnail maintenance gains the Convert outdated scope and names the
server's settings instead of its own quality and size fields (D131).
Overview's thumbnail row reads N missing, M outdated, K failed and
offers Convert outdated while previews are outdated.
The workspace decodes a tiny JPEG XL once: where it cannot, cards, the
Library and the inspector cover load the original for a .jxl preview,
and any preview that fails to load falls back to the original. The
viewer and downloads keep using the original (regression test).
README explains enabling JPEG XL; TESTING.md records D130 and D131.
Vito Sansevero
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