Intent to ship: Animation composite modes

[Brian Birtles]

Hi,

As of some time this week or next I intend to turn composite modes for
animations on by default for all channels. It has been developed behind the
dom.animations-api.compositing.enabled preference which has been on in
Nightly for 3~4 years now.

This is expected to ship in Chrome 84 (intent to ship:
https://groups.google.com/a/chromium.org/g/blink-dev/c/Wu4yPMznUw0/m/lgikzszpAwAJ
).

Safari have not announced concrete plans to ship this but have shown
positive signals.

Product: n/a
Bug to turn on by default:
https://bugzilla.mozilla.org/show_bug.cgi?id=1652676

There is no intent to prototype thread per se, but rather this feature was
developed as part of the work on Web Animations API announced in this
intent to implement thread from 2014:
https://groups.google.com/g/mozilla.dev.platform/c/3EXBgp26rJs/discussion

Best regards,

Brian