Not Windows Safe Mode, but Firefox's. With Firefox closed, press Windows + R and type in firefox.exe -safe-mode (with the space). If it launches normally the issue is with an installed extension, which can be identified through the process of elimination by disabling them one at a time and restarting Firefox. Otherwise it may be a corrupted Firefox profile, an issue addressed in the sticky thread at the top of this forum.
John
Hi, I'm a long time user of Mozilla Firefox, but lately I've been having problems opening the browser. I've noticed that the two times that it opened, it took about an hour or more. I've run antivirus, malware and spyware programs which indicate no problems. I've also uninstalled and reinstalled the latest version of Firefox. What should I do now??? Thanks!

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