In Windows 10, when you snap a window with a keyboard shortcut, normally you go and select with arrow keys and pressing enter another window to be selected and snapped next to it (or below it, etc.). Recently, I have this bug going on - the window choosing part is shown but the arrow keys do not move the selection from window to window and enter does not snap the other window.
When I right click into the area where windows for selection are present, suddenly the arrows and enter works. It seems as if the area lost focus and thus the arrows are not sent to it. However, I see nothing else having focus, nor pressing anything on keyboard does any action in any other window.
This happens 90% of the time. Sometimes, randomly, it works, but mostly it does not.