Crash bug, and workaround!
I will fix this as soon as possible (thursday?), but:
If you close the browser window while playing a level, the browser can crash. This is because Minecraft goes “OH CRAP, I’M GETTING SHUT DOWN!? I’D BETTER HURRY UP AND SAVE EVERYTHING TO DISK”, and if that takes too long, the browser gets upset.
To prevent this, always select “quit game” from the menu before closing the browser.
I will make the game only save the nearby area when quitting the game that way. This means you can lose changes to the level if you close your browser window, but at least it won’t crash the browser.
