In focal release of Ubuntu proper (GNOME Desktop) i was going trought the release on livestream using KVM based VM(libvirtd and virt-manager using default video settings provided by virt-manager, Host is ubuntu mate 20.04) and one of the things i was trying to show was fractional scaling which made my X11 session unusable. Screen turned black. Tryed different settings in Virt-manager for Video non worked.
Resolved the issue by switching to wayland session within which fractional scaling worked and i could disable it/switch to 100%.
When i after that switched to X11 session scaling was back to normal.
SideNote: when switching scaling in a VM i was running resolution was reseting back to normal.
https://youtu.be/0EFEGafZXDE?t=3400 link to the recording of a livestream on youtube with timecode enabled. (Video name: checking out Ubuntu 20.04 LTS, Channel: bigpod, timecode: 56:40)
Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:
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ubuntu-bug YOURFILE.crash
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3. If step 2 also failed then apply the workaround from bug 994921, reboot, reproduce the crash, and retry step 1.
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