Post

Firefox for Web Developers

@webdevs.firefox.com

Firefox 157 has landed, and includes a couple of useful CSS features: 🎉 at-rule() in @supports - lets you limit rules to browsers that support a given at-rule. 🎉 overscroll-behavior: chain - lets scrolling pass up to parent elements, but prevents UA effects like 'bounce' and overscroll. …And more!

developer.mozilla.orgFirefox 157 release notes for developers (Stable) - Mozilla | MDNThis article provides information about the changes in Firefox 157 that affect developers. Firefox 157 was released on September 29, 2026.

29/9/26, 1:15 pm13 reposts62 likes

Perhaps one day we’ll get cross-document view transitions in Firefox. But today is not that day. 😔 caniuse.com/cross-docume...

caniuse.comView Transitions (cross-document) | Can I use... Support tables for HTML5, CSS3, etc

Firefox for Web Developers

@webdevs.firefox.com

It's part of Interop 2026, so it's on its way. Although, scroll-driven-animations will land first.

chain is going to be handy for scroll areas inside modals.

@victorz.bsky.social

Is "chain" even documented yet on MDN?

Firefox for Web Developers

@webdevs.firefox.com

No, but it's on the way github.com/mdn/content/...

github.comAdded `overscroll-behavior: chain;` to shorthand and longhand properties by dletorey · Pull Request #45834 · mdn/contentDescription Updated the overscroll-behavior property page: Added overscroll-behavior: chain; to the Try it demo Updated the values to be clearer about their behavior and added chain Added an exam...

@victorz.bsky.social

Awesome! 🙇‍♂️🙏