Tumbleweed is stable for me, even though one does not choose a rolling release for stability. I understand your frustration, but what do you expect me to do? I just installed Xubuntu 18.04 LTS in a spare partition of my host, updated it, and installed VirtualBox. Running my TW KDE VM resulted in a graphics screen with a cursor only. That was with both 5.9.1 and 5.8.4 kernels. The only thing that changed was Xubuntu instead of a TW host. Why is this an openSUSE problem?