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I want to restore my previous session after i accidentaly opened a new one and didnt restore sessions so my previos session is now gone

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  • Last reply by cor-el

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I closed mozilla while playing a game cause i thought it was making it run slower,i then clicked a link in the game from the developers about a hotfix which openend a new window,i closed the window and forgot to restore session so now my session is entirely gone

I closed mozilla while playing a game cause i thought it was making it run slower,i then clicked a link in the game from the developers about a hotfix which openend a new window,i closed the window and forgot to restore session so now my session is entirely gone

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Best is to use one of these to close Firefox if you are currently doing that by clicking the close X on the Firefox title bar. That way you close all open windows at once.

  • "3-bar" menu button -> Exit (Power button)
  • Windows: File -> Exit
  • Mac: Firefox -> Quit Firefox
  • Linux: File -> Quit

Did you check "History -> Recently Closed Tabs/Windows"?


Firefox uses sessionstore.js in the profile folder to store session data. Sessionstore.js is only present when Firefox is closed. The sessionstore.js file is created from recovery.js when you close Firefox and is removed and copied to previous.js when you start Firefox to make is possible to restore the session at any time.

Backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data. Do NOT close Firefox when Firefox is already running.

You will normally find these files in the sessionstore-backups folder:

previous.js (cleanBackup: copy of sessionstore.js from previous session that was loaded successfully)
recovery.js (latest version of the sessionstore written during runtime)
recovery.bak (previous version of the sessionstore written during runtime)
upgrade.js-<build_id> (backup created during an upgrade of Firefox)

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.js to replace the current file (make a backup copy of the current sessionstore.js).

See also: