Game tried to go Fullscreen when i pressed start which isn't ideal for Webgl games and It froze to while doing it. Possibly best to keep it windowed and have the option for Fullscreen if the user wants to.
are you on Firefox perhaps? because for some reason that browser likes to go full screen no idea why chromium based seems to function better, you could also try full screen then press start and then play windowed. not sure exactly why that happened
