Trixie upgrade betatestings

That's very good, the upgrade tool will install nvidia drivers too... now the question is: why it didn't worked ? (kernel panic), as said before you can remove the v4l2loopback packages:

apr v4l2loopback-dkms

and then try to install nvidia from the elive nvidia installer, for that you can follow this howto: Nvidia Privative Drivers installation