Found somebody with a similar but not identical problem and the solution they found was"I had the same issue on Xubuntu 20.04.The reason is "Settings->Keyboard->Layout->Change layout option".Because I selected "Crtl+Shift" ...
Found somebody with a similar but not identical problem and the solution they found was"I had the same issue on Xubuntu 20.04.
The reason is "Settings->Keyboard->Layout->Change layout option".
Because I selected "Crtl+Shift" here, the pressed keys disappeared.
I changed the key setting, and it was fixed."
might be worth checking.
