well an error message about going full screen happens when trying to go to full screen and change the text color ofr comments
I have updated the page's font colour, I hope the cyan is better. Additionally, the full-screen error is a known firefox issue, un-maximize and press to full-screen again and it should work. Sorry for any inconvenience, I'll look into a more permanent fix for future builds / games. I have added a warning for firefox users at the top of the page.
I have updated the web build to remove any confusing screen-settings.
Thank you for your interest and feedback!