> but so far I haven’t seen any tooling (in macOS) to re-encode my existing photo library On Linux you can re-encode every single .jpg to .jxl and they'll deco

> but so far I haven’t seen any tooling (in macOS) to re-encode my existing photo library On Linux you can re-encode every single .jpg to .jxl and they'll decode bit-for-bit, to the original .jpg. On Debian and derivatives it's the libjxl-tools: the cjxl executable converts to .jxl and the djxl decompresses. Works flawlessly. P.S: as a sidenote there's zero reason anymore to serve a .jpg file to a browser when the browser supports .jxl files. That's just a waste of bandwith. (and if your stack cannot serve different files depending on the users' browsers' capacities, it's not much of a stack)