You're not alone. I updated Firefox yesterday and this same problem started again after I had repaired it last month. I did the same things I did last month but it's still not working completely. I decided if this is what is going to happen with every update, I will start using another browser. Like you, I tried Opera and it is working fine! If you find a fix for it, feel free to let us know. In the meantime, I will continue to use Opera but thanks for letting me know it's not just my system.