While sitting in the lobby of multiplayer in full screen mode, I pressed the escape key only to immediately get kicked to the BSOD. I had been playing for about 4 hours and had been noticing a a little stuttering in the battle loading animation. A memory leak perhaps? Playing from XP in chrome. Thanks Float
A little testing later, I got the same result (BSOD) while escaping out of the shop (while in full screen mode) in single player mode. Also, when the game crashed while in multi-player, all of the items from my multiplayer party inventory were transferred to my campaign party inventory.
You share total inventory and may have two different builds (from the same items) on your characters in single-player and multiplayer. However, I've started seeing the stuttering you mention in the battle loading animation. Quitting and resuming the entire browser isn't getting rid of it.