We need a dedicated object attached to the Document to track elements pending an update to their associated GraphicsLayer's accelerated effect stack and then generating such stacks through the render layer backing.
Pull request: https://github.com/WebKit/WebKit/pull/10999
Committed 261160@main (e3d89dcbb53b): <https://commits.webkit.org/261160@main> Reviewed commits have been landed. Closing PR #10999 and removing active labels.
<rdar://problem/106205692>