Firefox is getting the flag to turn it on in the next release, chromium just added it back now there is a rust decoder. The wheels are turning again. Browser support for jpeg xl is very much in progress again.
And it is already present in Safari (and more generally in iOS and macOS, as part of the standard OS graphics library):
* https://developer.apple.com/documentation/avfoundation/avvid...
* https://petapixel.com/2024/09/18/why-apple-uses-jpeg-xl-in-t...