The gnome-shell crash is bug 1964458 so I'll remove references to that
here.
Your log shows Xorg is failing to start on QXL with:
avril 05 16:15:58 ubuntu /usr/libexec/gdm-x-session[4265]: (EE) Screen(s)
found, but none have a usable configuration.
avril 05 16:15:58 ubuntu /usr/libexec/gdm-x-ses
** Summary changed:
- Jammy fails to boot to live session
+ Jammy fails to boot to live session in virt-manager with QXL
** Description changed:
Ubuntu Desktop Jammy 20220405
It fails to boot to the live session in virt-manager and gnome-boxes.
ubiquity-dm starts fine but the live sessi