200563 2019-08-08 22:19:10 -0700 [WinCairo][WK1] Accelerated Compositing is always disabled on Windows 10 version 1809 or newer 2019-08-19 18:59:30 -0700 1 1 1 Unclassified WebKit WebKit Misc. WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED https://bugs.webkit.org/show_bug.cgi?id=200493 P2 Normal --- 1 fujii webkit-unassigned oldest_to_newest 1559799 0 fujii 2019-08-08 22:19:10 -0700 [WinCairo][WK1] Accelerated Compositing is always disabled on Windows 10 version 1903 1. Start MiniBrowser 2. Open WebKitLegacy Window 3. Go to https://webkit.org/blog-files/3d-transforms/poster-circle.html 4. Poster Circle show flatly AcceleratedCompositingContext::acceleratedCompositingAvailable creates testWindow in the outside of screen. Nothing is drawn. Windows 10 version 1803: OK Windows 10 version 1903: NG WebKitTestRunner has the same issue (Bug 198820). 1559815 1 fujii 2019-08-08 23:31:04 -0700 Windows 10 version 1809: NG 1562889 2 fujii 2019-08-19 18:59:30 -0700 Reverted r179962 in r248885. Closed.