I’m not much hoepful, but… just in case :)
I would like to be able to start a second session in a window of my current one (I mean a second session where I log in as a different user, similar to what happens with the various ctrl+alt+Fx, but starting a graphical session rather than a console one).
Do you know of some software that lets me do it?
Can I somehow run a KVM using my host disk as a the disk for the guest VM (and without breaking stuff)?
I’d imagine you could run a VNC server, and then just login from the same PC. This kinda what you’re looking for?
There are some limitations, like I don’t think hardware acceleration would work, for example.
whats a vnc server o.O
Virtual Network Computing. It’s basically an alternative to remote desktop.
It’s a lot easier with Wayland and hardware acceleration works, see my solution. It does a proper login session and starts the whole DE exactly the same way as if you logged in from a tty too so everything just works as expected there. Wayland devs use that a lot for testing and development so it’s quite well supported overall.