virtualbox.org

Does somebody know how to do that? There seem to be a lot of dependency problems...

Thx for feedbacks.

Guest Additions in a Debian guest? Probably not a Windows Hosts question...
Take a look at this and take another shot at the question.

I think "host" means the system where VirtualBox runs...? Or is "host" the vm itself?

"Host" is the physical PC, yes. Virtualbox gets installed on the host.
The "guest" is the VM, and Guest Additions go in the guest OS. There's an ISO provided with Virtualbox for the Guest Additions. Use the provided ISO on Linux guests - the distros like to fork Virtualbox & the GAs, and the forum gurus don't know what was changed in the fork.

ok, thx, will try it..

Debian (in non-GUI mode, as a server or something like that) works also well with the strech-backports kernel and NOT guest additions drivers - at least no problems until not.

And there is an advantage too: You will not need to re-install the drivers when you update from 5.2.x to 5.2.x or from 6.0.x to 6.0.y!! ;-)