Whenever I press the fullscreen button, my cursor flashes between the top-left corner and where it should be, during this time the game doesn't respond to input. (this is on a chromebook).

It used to work fine before the latest update (to bbs I think?) so if there was a way to access that version of the player it would work fine.

Can confirm, I have the same issue on Chrome. However, it seems to work on Firefox? Except there it forcibly pulls the cursor to the center of the screen where it flickers endlessly.