How do you quit the game (using in-game menus)? There seems to be every option but that and all can do in fullscreen (apart from turning it off) is Alt+F4.
BTW, the game doesn't save my options: it starts of windowed and with Type A controls.
I'm worried any further questions I have will lead me to Discord, which my client is getting filled with Servers I join just for that purpose and never use again...