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How to recover session using "upgrade.js" ?

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My computer auto-restarted overnight while I slept, come morning time my wife was checking her emails online... which caused my previous session to be lost. I have some important tabs that I need to recover, and thankfully I was able to find my session in one of the "upgrade.js" files.

I copied the "upgrade.js" file and renamed it to "sessionstore.js" as mentioned elsewhere on this support forum. It has not worked, not sure if my version of Firefox is incompatible with that advice... or... if there are details missing with regards to all the steps I have to take to restore the session.

Please advise, I need to recover my tabs ASAP

My computer auto-restarted overnight while I slept, come morning time my wife was checking her emails online... which caused my previous session to be lost. I have some important tabs that I need to recover, and thankfully I was able to find my session in one of the "upgrade.js" files. I copied the "upgrade.js" file and renamed it to "sessionstore.js" as mentioned elsewhere on this support forum. It has not worked, not sure if my version of Firefox is incompatible with that advice... or... if there are details missing with regards to all the steps I have to take to restore the session. Please advise, I need to recover my tabs ASAP

Chosen solution

I failed to pay attention to detail earlier...

Instead of putting the renamed file into the main profile folder I kept trying to get it to work by placing it in the "sessionstore-backup" folder.

Problem is solved, thanks

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Firefox uses sessionstore.js file in the profile folder to store session data, but this file 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.

You can backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data. You can 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: http://www.ghacks.net/2014/06/27/mozilla-launches-improved-session-restore-firefox-33/

You can use this button to go to the current Firefox profile folder:

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Chosen Solution

I failed to pay attention to detail earlier...

Instead of putting the renamed file into the main profile folder I kept trying to get it to work by placing it in the "sessionstore-backup" folder.

Problem is solved, thanks