Public bug reported:
The problem happens randomly and every time it keeps for one or two
minutes.
During that period, keyboard input gets stuck in any window text input
widgets, for example, typing letters, enter key, backspace, and moving
input cursor with arrow keys. But with other window widge
I just reproduced the problem. One more detail I want to say, both my
builtin display and the external monitor's resolution are 1920x1080
** Attachment added: "the output of 'xrandr --verbose > xrandr2.txt'"
https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1905648/+attachment/5438731/+fi
