updated Tumbleweed a few days ago to build 20210425.

Reboot ended in a command prompt rather than firing up KDE.

Using Kernel 5.11.4 made it work again.

Spent some time today in figuring out what the problem is and it seems the nVidia repository is out of sync - the kernel used there is still at 5.11.11 rather than 5.11.16.

Juergen