I have this problem, as well, since the upgrade to 4.0.1. After the upgrade, I found several 'Recovered Files' in my Trash. On taking a look, they all had to do with the Crowdstar app. Happy Aquarium, I believe, but there are several folders of them. Some of them could have to do with Zynga's FarmVille.

However, after repeated problems, I installed Chrome 10. to see if the Facebook apps. would work. They did, without problems. That tells me the folders in Trash shouldn't have anything to do with whether they operate or not but it has something to do with something Firefox has done, or not done, with this upgrade. Frankly, I'm baffled and more than a little annoyed. :/

However, thinking back to the upgrade, it happened suddenly while I was on the phone with AppleCare on another matter. It was they who suggested I needed to upgrade my browser and I did it immediately, on-the-spot. It wasn't what you would call a 'clean install' because I was on the phone but also online with AppleCare. The process went so fast, I remember there were things about the installation that didn't quite seem right and I do remember that the earlier version of Firefox was not removed prior to the upgrade. Is there any chance something could be out-of whack because of this? If so, I need to know how to save my passwords, bookmarks, profile, and any other critical info that would need to be transferred.

Each time I update Firefox I have problems with my Zynga games. I can't move around in the game, various things won't work and sometimes get booted off. Could you fix this problem for me?

I had forgotten about my post in here but I see there is not too much in the way of possible insight, however, what I have found since posting the initial post is that I don't have any problems EXCEPT with Zynga's FarmVille app. I have upgraded Firefox to v. 8.0.1 now and Facebook seems to run smoothly as do the other apps. that I play. I use an iMac and do find that if I use Safari for playing the apps., there are fewer problems but I need to give the new upgrade more use before saying I wouldn't use it over Safari now. I like the security of Firefox...always have. I do have to note that many of the difficulties with Zynga's apps. are Zynga's. Not Facebook nor the browser. One thing you have to remember is to clear your cache frequently before logging into Facebook, if you play many apps. on a regular basis.