JPEG XL is a royalty-free image raster graphics format aiming to replace existing raster formats:
https://en.wikipedia.org/wiki/JPEG_XL

Software support is generally good already and still improving. The only outliers are web browsers.
None of the major browsers have it enabled by default yet and some, like Chrome, are already planning to drop it despite the huge interest and JXL being regarded superior by the community/users to existing formats.

Some more articles, discussions and sites:

• https://jpegxl.info/
• https://www.frost.cx/2022/why-jpeg-xl
• https://news.ycombinator.com/item?id=33399940
• https://www.reddit.com/r/firefox/comments/yi4rr5/jpeg_xl_is_gaining_traction_but_suddenly_is_being/
• https://www.reddit.com/r/programming/comments/yib184/google_chrome_is_already_preparing_to_deprecate/
• https://cloudinary.com/blog/the-case-for-jpeg-xl (HN comments)