Intent to Ship: :has-slotted pseudo class

[Keith Cirkel]

Summary: The :has-slotted selector

Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1940691

Specification: https://drafts.csswg.org/css-scoping-1/#the-has-slotted-pseudo

Standards Body: CSS WG

Platform coverage: All

Preference: layout.css.has-slotted-selector.enabled

Devtools bug: N/A

Other browsers:

  - Blink: I2S (https://groups.google.com/a/chromium.org/g/blink-dev/c/o3ja7zaKuls).

  - WebKit: Supportive (https://github.com/WebKit/standards-positions/issues/404).

web-platform-tests: Tests available at https://wpt.fyi/results/css/css-scoping?label=experimental&label=master&aligned

Gecko-only tests were introduced: N/A

I intend to ship this in Firefox by default - my understanding is that all open issues in the CSSWG have been resolved and the feature works as intended. Chrome also has an I2S, and WebKit has a patch ready. The Web Components Community Group is supportive of this feature.

If anyone has any concerns please let me know!

Happy browsing.