Space to start is rough for browsers because scrolls the page. The player is then scrambling to get the board back in view before the ball is out of bounds – at least it happens to me.
I just found Shift+Space worked to trigger game start and kept browser page from scrolling.
Hi! Thanks for taking a look and finding the workaround!
I noticed this on my last test and changed it to [s] (and [r] for restart), but I wasn't able to sneak the change in before the deadline.