The game doesn't work in window mode because the buttons to continue are below the screen. Switching to full screen only works until the third screen, then the text and instructions are below the screen again.
You're right, and thank you for saying so instead of just closing the tab. Cause: all three rooms were stacked down one long page, and itch's frame doesn't give the player a scrollbar. Fixed: rooms now swap instead of stacking, and the whole thing scales to fit whatever window you give it, so the continue buttons stay on screen. The new build is live on the page. If room three still clips at your window size, tell me the size and I'll go after that too.