When I am on websites (many different ones such as Facebook, Yahoo mail, and many other sites that I visit) Facebook slows down to the point where it takes several minutes for a 'click' to register, or the program locks up completely and I have to force quit and start over. I haven't had this problem until I upgraded to Firefox 5.0. Now, it happens all the time. I love Firefox, and have always preferred it to other browsers...until this started happening.