Intent to Ship: Scroll-driven Animations

[Boris Chiou]

As of Fx159, I intend to turn Scroll-driven Animations on by default on all platforms. It has been developed behind the "layout.css.scroll-driven-animations.enabled" preference. Google Chrome has shipped it since Chrome 115, and Safari has shipped it since Safari 26.

Bug to turn on by default: 
https://bugzilla.mozilla.org/show_bug.cgi?id=1324602

Standard: 
https://drafts.csswg.org/scroll-animations-1/

Intent to Prototype Thread:
https://groups.google.com/a/mozilla.org/g/dev-platform/c/d8k74ywuFNQ/m/GhdIaDDbCQAJ

Note that the feature name was updated from Scroll-linked Animations to Scroll-driven Animations.