ugjdgdto [1] filed a deletion request for ffmpeg-jxl [2]: Since version 2:6.0-4, ffmpeg in [Extra] is already built with JXL support, so this package is no longer needed.
[1] https://aur.archlinux.org/account/ugjdgdto/ [2] https://aur.archlinux.org/pkgbase/ffmpeg-jxl/
