AV1 won an Emmy! We're proud to be part of the Alliance for Open Media, where the codec was developed. But the story's not over… AV2 is just around the corner.

https://blog.mozilla.org/en/mozilla/av1-video-codec-wins-emmy/

Another API proposal from TPAC: CSS routes and navigation queries, meaning less JavaScript is needed for view transitions!

https://drafts.csswg.org/css-navigation-1/

https://github.com/w3c/csswg-drafts/issues/8685#issue-1653949919

We have Custom Elements, but do we also need Custom Attributes?

This was discussed at TPAC. Is it something you'd like on the platform?

https://github.com/WICG/webcomponents/issues/1029

Out-of-order HTML patching, another proposal from TPAC, lets HTML be presented non-linearly, and a single file can update multiple parts of the page.

Would this feature be useful to you?

streamHTMLUnsafe() was presented at TPAC last week. Finally, an API that lets you easily use the streaming HTML parser from JavaScript! Here's a quick overview:

New in Firefox nightly (146.0a1 2025-10-19): large lists of unused CSS custom properties are collapsed by default.

This not only reduces clutter, it also massively speeds up the rendering of the inspector panel in some cases.