How exactly are you supposed to use a format that isn't supported?
How would 5% of sites ever get to use JXL if it isn't supported in web browsers?
How would 5% of sites ever get to use JXL if it isn't supported in web browsers?
Here's one: https://github.com/niutech/jxl.js
Demo: https://niutech.github.io/jxl.js/
Libjxl's own WASM build: https://github.com/libjxl/libjxl/tree/main/tools/wasm_demo