I was just playing with new xubuntu 20.04 beta in Hyper-V (W10 64bit), both generation 1 and generation 2 had the same behaviour.
I made clean installation of xubuntu, logged in and everything works without any problem. I left the hyper-v session for several minutes (and worked in another Windows app). After going back to xubuntu, neither mouse nor keyboard were functional. I can see the screen I left (no screen saver was activated (default install without any changes), current time is still updating), but neither mouse clicking nor keyboard makes any response. While moving the mouse to the edge of any app window, I can see resize mouse icon, but resizing doesn't work. Hyper-v ctrl-alt-del doesn't work. Soft shut-down works, after reboot I can do anything without any problem (until leaving hyper-v session and going back later).
I tested it several times and this problem happens exactly after 5 minutes of inactivity (default time for screensaver), mouse reacts on moving, mouse over effects are working, but mouse clicking & keyboard input are not working.
There is probably some bug in the beta... Can anybody confirm that the behaviour is the same on another computer?
Z.
This problem is also in final Xubuntu 20.04 (Hyper-V, Win10 64bit).
After 5 minutes screensaver doesn't start, but the virtual stops responding to keyboard and clicking. Mouse movements (and mouse over effects) are working.
When I disable screensaver there is no problem.