Firefox is not responding
Your Firefox Browser not responding. It stops for few seconds when you open any site.
Don't frustrate and try the below solution it would really help you
Go to Help Tab and Select Troubleshooting Information.
On the right side of the page, under the "Reset Firefox to its default state" section, click the "Reset Firefox ..." button.
Firefox will save some old browser information to a folder on your Desktop, and then reset the web browser to the Firefox defaults. (Your Bookmarks won't get deleted). I don't think I'll need this folder for anything and I'll just delete it in a couple of days.
Firefox will restart and work normally again!