While debugging https://github.com/WebKit/WebKit/pull/3802#issuecomment-1232898953 I found out that video elements don't render any image inside LayoutTests. This is particularly problematic for any tests relying on visual output, such as reftests. This is easily reproduced with compositing/video/video-border-radius-clipping.html, which should output a single big green frame -- and does so in the minibrowser -- but appears white when ran in the test runner, for instance, in this EWS results: https://ews-build.s3-us-west-2.amazonaws.com/GTK-WK2-Tests-EWS/dbb1766c-24083/results.html Passing --wrapper='env GST_DEBUG=webkit*:DEBUG' to run-webkit-tests shows the likely culprit of this, a failure to get a GL context: 0:00:03.530073170 56 0x7f6ac0 WARN webkitmediaplayer PlatformDisplayGStreamer.cpp:115:tryEnsureGstGLContext: Failed to fill in GStreamer context: could not retrieve fbconfig from its ID 0x42. Wrong Display or Screen?
compositing/video/video-border-radius-clipping.html is passing though? At least here in the default XvFB setup and also when I pass --display-server=wayland
The GL sink is now replaced by another sink, re-titling the bug. I can now reproduce this issue here, the actual rendered frame is white instead of green. Zan mentioned this could be a TextureMapper bug. To be confirmed.
Seems like this was fixed... compositing/video/video-border-radius-clipping.html is passing in XvFB and host wayland compositor.