After downgrading back to 88. I have no tabs, no bookmarks, no . . .

Look on your desktop. Do you see a folder called; Old Firefox? Look inside. Look for the folder with the latest creation date.

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be there? Also, open the profile folder in your file explorer.

https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

Firefox 89 crashes almost instant, even in safe mode.

If you can't get Firefox to open, you will have to do this the hard way. https://support.mozilla.org/en-US/kb/mozillacrashreporter

Open the file browser / explorer on your computer. Note: You may have to enable Show Hidden Folders / Files. Enter this in the address bar;

Windows: %APPDATA%\Mozilla\Firefox\Crash Reports\submitted Win 7/Vista: C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Crash Reports\submitted Win XP/2000: C:\Documents and Settings\<username>\Application Data\Mozilla\Firefox\Crash Reports\submitted Win 10: Press <Windows> + R on the keyboard. A Run dialog will open. In the Run dialog, type %APPDATA%\Mozilla\Firefox\Crash Reports\submitted <Enter>

Mac OS: /Users/<username>/Library/Application Support/Firefox/Crash Reports/submitted Linux: /home/<username>/.mozilla/firefox/Crash Reports/submitted

Copy the most Recent 5-7 File Names in the folder. Press the Reply button. Now go to the reply box and paste them in.

How about release a stable upgrade that has been properly tested. Allow for backups to be used from any version. Not act like suddenly the version from a week ago is a huge security risk, while you fix what you put out that doesn't work. Instead of me running thru hoops fixing what Mozilla broke. I've sent crash reports. I'm not sending them here. Also quite interesting, no actual email or contact number for Mozilla themselves.

Thanks for useless info. As if I haven't run thru this already. Firefox won't use session information from a higher version because it may be "corrupted to a lower version". So after the memory leak, I assume this is what it is because for a day it was fine. All my session backups become corrupt to the 89 version. Once I revert, version 88 sees my profile information as unusable. So actual solutions. Not a few standard response url that I've already reviewed and don't work.

Hi,

The people who answer questions here, for the most part, are other users volunteering their time (like me), not Mozilla employees or Firefox developers. If you want to leave feedback for Firefox developers, you can go to the Firefox Help menu and select Submit Feedback... or use this link. Your feedback gets collected by a team of people who read it and gather data about the most common issues.

You can also file a bug report or feature request. See File a bug report or feature request for Mozilla products for details.