Intent to Prototype: Scoped Styles (@scope)

[David Shin]

Summary: Scoped styles let users limit styling to DOM subtrees (Which can be further limited to a depth, if scope-end is specified as well).

Bug:  Bug 1830512 (Metabug, basic functionality to be added in Bug 1886441)

Standard Draft: https://drafts.csswg.org/css-cascade-6/#scoped-styles

Standard Positions: https://github.com/mozilla/standards-positions/issues/472

Platform Coverage: all

Preference: layout.css.at-scope.enabled

Other Browsers: Shipped - Chrome 118, Safari 17.4

[Nicolas Chevobbe]

Thanks David.

We also have Bug 1873029 to add support for @scope in DevTools