Dr. Nikolaus Klepp wrote:

> VirtualBox is not available for beowulf/buster - that's why I have to use
> virt-manager :( BTW, do you know how to set the screen resolution to
> 1024x768 in virt-manager?
> 

I don't know about you, but I see here it says "Debian 10"

VirtualBox 6.0.12 for Linux

     Ubuntu 18.04 / 18.10 / 19.04 / Debian 10 

https://www.virtualbox.org/wiki/Linux_Downloads

regards