Comment 4 for bug 2000739

That is interesting, but also usually hard to debug (at least for me graphic issues always have the aura of mystery).
I was giving the same use-case a try so that we have more measurement points.
Installed the current 22.04.1 ISO in the default (minimal install, no customization) and set its resolution to the native one of my screens.

Then I booted that disk in different viewing modes to check how it behaves.

Display types:
- default: no display type specified (back in 20.04 it might have been sdl for you anyway)
- spice: -spice port=9999,disable-ticketing=on connect via spicy -h 127.0.0.1 -p 9999
- vnc: -vnc :1 connect via krdc vnc://127.0.0.1:5901
- gtk: -display gtk
- sdl: -display sdl
- virt-manager: sets up connecttions automatically, uses a spice based viewer

Driver QXL
- default - working fine
- spice - working fine
- vnc - working fine
- gtk - working fine
- sdl - working fine
- virt-manager - working fine

Well, I planned to go into other drivers, but since it works just fine with the reported driver I did stop here.
Hmm, we need to find what is different for you ... :-/

@markus - is this a one time thing for you e.g. right after the resolution change and goes away e.g. after a guest reboot or is it permanent? (to make sure we try to reproduce the same)

@markus - you said you set it to the native resolution of the screen - maybe it depends on that. I've used normal full-HD 1920x1080 what did you use?

@markus - For the sake of trying if there is a fix even thought we do not know which one. Would you be able to try the backport of qemu 7.0 from https://launchpad.net/~canonical-server/+archive/ubuntu/server-backports ?