Once we have scrollbar layers (from bug 78872) and a way to encapsulate paint logic from scrollbars (bug 78028), we need to add a some logic to scrollbar layers that will let them execute this painting logic on the compositor thread.
Created attachment 128025 [details]
Please ignore patch
(In reply to comment #1)
> Created an attachment (id=128025) [details]
Just doing some cleanup. This will be fixed with 78872?
Yeah, this is a duplicate of 78872.
*** This bug has been marked as a duplicate of bug 78872 ***