It's pretty buggy. When I tried to expand the game, I quickly realized that was a mistake when I was met with just a black screen. Pressing escape didn't bring back the text or anything, either.
I also think the volume button is just there to make the game unclickable sometimes. I also couldn't use the number keys to the right of my keyboard at the very beginning (num lock was indeed on) but the number keys to the left worked just fine. However after messing with the volume button, I couldn't even get Space Bar to work. I guess just be careful?