2060755 - Set layout.css.supports.at-rule.enabled for release (@supports at-rule())

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, enhancement)

Description

[Sajid Anwar [:sajidanwar]]

Ship the at-rule() function for @supports by enabling layout.css.supports.at-rule.enabled for release builds.

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Release Note Request (optional, but appreciated)
[Why is this notable]: New CSS feature, parity with Chrome
[Affects Firefox for Android]: Yes
[Suggested wording]: Firefox now supports the at-rule() function for @supports. This allows authors to detect for browser support of specific at-rules, such as @supports at-rule(@scope).
[Links (documentation, blog post, etc)]:

• https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules/@supports#at-rule
• https://www.bram.us/2026/03/15/at-rule/

Comment 1

[Sajid Anwar [:sajidanwar]]

Attachment: Bug 2060755 - Set layout.css.supports.at-rule.enabled for release. r=#style

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/baca6d1fcb19
https://hg.mozilla.org/integration/autoland/rev/d91cd39c43eb
Set layout.css.supports.at-rule.enabled for release. r=firefox-style-system-reviewers,emilio

Comment 3

[agoloman]

https://hg.mozilla.org/mozilla-central/rev/d91cd39c43eb

Comment 4

[Dianna Smith [:diannaS]]

Added to 157 release notes

Comment 5

[Dave Letorey]

Associated Pull Request

• Firefox Release