Have you went to Firefox Button => Help (Hover over) => Troubleshooting Information? Then hit the reset button.

Try starting Firefox in Firefox's safemode. As a diagnostic / troubleshooting step that may help you. It may also enable you to get into the troubleshooting page.

• N.B. also try navigating directly to about:support by keying it into the address bar.

I am not sure about Mac s but they have some sort of safe mode. It may also be worth trying that.

A reset button does not appear nothing loads when j clicked troubleshooting

I can't even type about :support into the line as another helper suggested and on startup it goes too fast to allow me to choose safe mode

I can't even type about:support into the address line it's so unresponsive and startup is too fast to be able to select safe mode

You only see the reset button on the "Help > Troubleshooting Information" page if you use the profile that is marked as Default=1 in the profiles.ini file.

If you do not have the "Reset" button then either use the Profile Manager to create a new profile or use the Profile Manager to start with the current default profile to get the reset button in Firefox.

• http://kb.mozillazine.org/Profile_Manager
• https://support.mozilla.org/kb/Managing+profiles