Mir switches away from the current VT when ALT+FXX is pressed. During that key sequence the alt modifier is pressed. While away and mir does not receive the alt release. When you switch back to mir there is a chance that mir is not receiving the alt release either.
So switching away and back to mir makes the alt key stick...
Mir switches away from the current VT when ALT+FXX is pressed. During that key sequence the alt modifier is pressed. While away and mir does not receive the alt release. When you switch back to mir there is a chance that mir is not receiving the alt release either.
So switching away and back to mir makes the alt key stick...