I just upgraded to Firefox 4. Just prior to upgrading I was able to play all my games on facebook without issue. After upgrading (and restarting my computer), when I try to get into certain games I'm having trouble. Some of the games load just fine but other games will either start to load then stop and the page goes blank or remain on the loading screen without ever actually completing the load. I checked the Flash player Global Storage Settings panel and everything there was as it should be.