I am using a Lenovo laptop with i5 processor, upgraded its OS from Windows 7 Home Basic to Home Premium. I also have Norton360 and TuneUp Utilities (latest versions, 2012).
Firefox 11 was running OK, but because I had many add-ons, I decided to uninstall it and get myself a fresh browser. So, I did that with Revo Uninstaller Pro.
After the re-installation, every time I run Firefox the address bar doesn't take any input from the keyboard. The program itself accepts the mouse clicks on menus for a short time, before it freezes completely!
After I press Ctrl+W, it adds +1 to the number of opened tabs. Firefox opens 2 tabs on start up, one for the homepage and the other on Mozilla site. But it asks me "do you want to all the 3 opened tabs?". It does the same when there is only one tab opened.