Hello,

The Refresh feature (called "Reset" in older Firefox versions) can fix many issues by restoring Firefox to its factory default state while saving your bookmarks, history, passwords, cookies, and other essential information.

Note: When you use this feature, you will lose any extensions, toolbar customizations, and some preferences. See the Refresh Firefox - reset add-ons and settings article for more information.

To Refresh Firefox:

1. Open the Troubleshooting Information page using one of these methods:
   • Click the menu button , click help and select Troubleshooting Information. A new tab containing your troubleshooting information should open.
   • If you're unable to access the Help menu, type about:support in your address bar to bring up the Troubleshooting Information page.
2. At the top right corner of the page, you should see a button that says "Refresh Firefox" ("Reset Firefox" in older Firefox versions). Click on it.
3. Firefox will close. After the refresh process is completed, Firefox will show a window with the information that is imported.
4. Click Finish and Firefox will reopen.

Did this fix the problem? Please report back to us!

Thank you.

This is a bug in Firefox 67 and can occur with some specific settings.

Are you possibly using "Delete cookies and site data when Firefox is closed" and also "Clear history when Firefox closes"?

• Options/Preferences -> Privacy & Security:
  Cookies and Site Data:
  [ ] "Delete cookies and site data when Firefox is closed"
• Options/Preferences -> Privacy & Security:
  Firefox will: "Use custom settings for history":
  [X] "Clear history when Firefox closes" -> Settings

If you do then try to disable at least one of these.

Also see :

https://bugzilla.mozilla.org/show_bug.cgi?id=1554167