Earlier today I was using Mozilla just checking my e-mail and stuff. It unexpectedly quit, fine, no big deal, just restart it like usual and carry on. Except now it won't start up. It just stays on the grey Apple screen but the little circle spinning thing never comes up. I can start up under Safe Mode by holding down the shift while starting up, but that's it. This happened once before so I started up under Safe Mode and deleted some things I had recently added, restarted, and all was well again. I did the same thing this time, but all is not well. Any suggestions??