Seemingly at random, but as often as daily, the fullscreen/window setting keeps bugging out.
I start the game menu, it starts in some strange window resolution which doesn't cover top part of the screen.
I check the settings, both "Ingame/Menu Display Mode" are set to "Fullscreen".
Starting a game match does not fix the problem.
Only way to fix this is to set one of the settings to "Windowed" and then again to "Fullscreen".