Just installed xubuntu 20.04. Same problem. Running sudo apt remove gstreamer1.0-vaapi and sudo apt autoremove provided the work-around.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1784242 Title: Totem displays a green screen on H264 videos with gstreamer1.0-vaapi To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gstreamer-vaapi/+bug/1784242/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs