Partially restores what the cowardly Mozilla Foundation removed: support for the superior, industry-approved, backwards-compatible, open standard JPEG-XL.

(So much for driving standards compliance and being a meaningful alternative to monopolies, huh? Thanks, Mozilla.)

Unfortunately, animation is apparently not supported by this add-on at this time (September 2024) -- as tested on the jpeg xl test page.

Sadly it requires JS to be enabled for the webpage that embeds JXL images, i.e. when you're using NoScript you will not see JXL images, unless you've enabled JS execution for the page.

Secondly, it doesn't seem to support animated JXL.

Thirdly, Firefox has removed native JXL support (it can no longer be enabled via about:support). Shame on you Mozilla.

Works well. Doesn't seem to support animations as you can see illustrated from this test page -- https://jpegxl.info/test-page/

Doesn't work in LibreWolf(from box, but i remember before is work), firefox all work.
But this is a crutch, the original jpegxl is converted to png and you don't get the benefit of its specification + have worse perfomance with reconverting

Does not actually show original JXL, but seems to convert it to PNG (lossless). Complications may occur, such as with complex or unsupported metadata. But this is probably still a decent improvement (still testing), and about as good as it gets until Mozilla properly implements support for JPEG XL.

Does what it says. Can't wait till JPEG XL reaches its peak. Being a image format first it will outlive video based image formats like AVIF.