Alright, that clarifies the chair grabbing part.
I played the browser version, and set the fullscreen from the title page in game. I actually can't find the overlay option. There's a setting to be enabled on Itch for this I guess. Right now the in-game fullscreen option acts more like a toggle. If it's fullscreen and I hit "Escape" the game goes back to windowed, but the setting is still in the "On" state. Then changing it to "Off" enables fullscreen, etc.