ClutterActor fires motion-event when windows get added or removed
The motion-event of a ClutterActor will get fired without any mouse movement when a window is added or removed from the stage.
To reproduce, launch an app after a timeout (sleep 10 && gnome-calculator
), open the alt-tab switcher and select something using the keyboard while leaving the pointer hovering over some other item of the switcher, then wait for the new window getting opened. A motion event will get fired and the item the pointer is hovering over will be selected without any mouse movements.