Without an appropriate ImageBufferPipe implementation, OffscreenCanvas falls back to posting the image to be displayed to the main thread.
<rdar://problem/99902985>
Pull request: https://github.com/WebKit/WebKit/pull/5795
Committed 257696@main (f92c75b5eb3f): <https://commits.webkit.org/257696@main> Reviewed commits have been landed. Closing PR #5795 and removing active labels.