Freezing of virtual box after putting host to sleep (Whonix

Already had some problem with Whonix 10 + putting host into sleepmode (Whonix Forum). And now having a some problems with Whonix When recovering from sleepmode on my host, some times the Gateway (mostly) or the Workstation (once) is completely black and unresponsive.

The blackness seems to be a new Whonix 11 function when you don’t use the Workstation/Gateway for a few minutes, normally when clicking the Workstation/Gateway it becomes active agian. However after the host recovers from sleepmode it some times freezes.

On one occasion my Gateway had a (partial) kernel panic instead of a completely black screen:
Freezing user space processes … (elapsed 0.001 seconds) done.
Freezing remaining freezable tasks … (elapsed 0.000 seconds) done.
Suspending console(s) (use no_console_suspend to debug)

Are these problems with sleepmode to be expected?

Already discussed here: