We're sorry to hear that Firefox is crashing when you open it. Please do the following to give us crash IDs that will help us understand more about the crash.

1. Click the Finder icon in the dock. On the menu bar, click the Go menu, hold down the option or alt key and select Library. A window will open containing your Library folder.
2. Open the "Application Support" folder, the "Firefox" folder, the "Crash Reports" folder and finally the "submitted" folder.
3. Open the 5 most recent files with a text editor and copy the IDs.
4. Paste each ID with bp- into the reply window on the forums.

Thanks in advance!

You can find more information and troubleshooting steps in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

You can copy certain files with Firefox closed from the profile folder to backup your personal data. Note that best is to avoid restoring a full profile folder and only restore important files that are safe to restore/transfer.

Primary location used for the main profile that keeps your personal data (Root Directory on about:profiles).

• ~/Library/Application Support/Firefox/Profiles/<profile>
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

• bookmarks and history: places.sqlite
• favicons: favicons.sqlite
• bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
• cookies.sqlite for the Cookies
• formhistory.sqlite for saved autocomplete Form Data
• logins.json (encrypted logins) and key4.db (encryption key/primary password) for logins saved in the Password Manager
• cert9.db for certificates stored in the Certificate Manager
• persdict.dat for words added to the spell checker dictionary
• permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
• sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)

There is no firefox folder under application support. I will reinstall again to see if it will create the folder and a new profile. So far nothing has worked.

Deleted FF from applications. Reinstalled. It now opens. BUT how do I recover the old profile? Or atleast all my stored passwords and bookmarks?