Firefox 157 will ship JPEG XL on all platforms using a Rust decoder Mozilla required before it would ship the format

Sources: primary, dev-platform thread, discussion
Summary: Mozilla announced intent to ship JPEG XL in Firefox 157 on all platforms. The decoder is written in Rust, which Mozilla set as a condition before it would ship the format. Mozilla put that challenge to the JPEG XL team at Google Research, which built jxl-rs, now the core of Firefox's support. The intent-to-ship notice ran on the dev-platform list. Mozilla projects that the format will be supported across browsers before the end of the year, resting that on Chrome stating an intent to ship and on a partial Safari implementation that lacks the progressive rendering the post highlights. Chrome has not shipped it.
Why it matters: Mozilla's Rust condition sets a precedent for gating new C++ attack surface behind a rewrite, and if the projected Chrome and Safari support lands, a second modern image format changes the encode decision for anyone serving images.