We need something more fine-grained than "delegates scrolling" with macOS UI-side compositing.
<rdar://problem/100995741>
Pull request: https://github.com/WebKit/WebKit/pull/5206
Committed 255382@main (cfc548338e84): <https://commits.webkit.org/255382@main> Reviewed commits have been landed. Closing PR #5206 and removing active labels.