Was playing bubble witch saga on FaceBook. The game suddenly shrunk the display to unreadably small dimensions. I restarted FireFox, and when I tried to login to FaceBook again the login page was unreadably small. Even if I maximize the FireFox window, the login screen occupies only a tiny space in the middle of the window. This problem effects no web sites other than FaceBook. If I start FireFox with a different profile, the FaceBook problem does not occur. Sounds like the game left something nasty in the affected profile directory. I've cleared the cache and recent history for the profile, but that didn't help. Suggestions?