It looks like your graphics driver is probably relevant because with an
Intel GPU and the same software the problem does not occur.
** Tags added: focal nvidia
** Summary changed:
- this webm video makes Totem's window flicker
+ Transparent pixels are rendered incorrectly by Totem (leave
The problem actually seems to occur with any video that contains
transparent pixels. Here is for example a VP8-encoded fully transparent
video with which I can reproduce the problem.
The video displays perfectly fine in vlc, mpv, and firefox (the
transparent pixels are simply displayed in black).
This is what the bug looks like. The bug does not appear on screenshots,
so I filmed my screen.
** Attachment added: "screen_capture.mp4"
https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/1893572/+attachment/5405892/+files/screen_capture.mp4
** Package changed: compiz (Ubuntu) => totem
