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How do I restore a previous session from an Old Firefox Data folder?

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  • 15 have this problem
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  • Last reply by DerekSands

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There was a power blackout today while I was booting up Firefox and the computer shut down instantly. Later, when I tried to open Firefox again, it started glitching out, with the Restore Session option only resulting in empty tabs. I refreshed Firefox and now I have a 'Old Firefox Data' folder.

I have a sessionrestore-backups folder in that folder, with a 'previous.js' file. How do I use this file (or any of the others in the folder) to gain access to my lost session? Is it possible at all?

Thanks for any and all help.

There was a power blackout today while I was booting up Firefox and the computer shut down instantly. Later, when I tried to open Firefox again, it started glitching out, with the Restore Session option only resulting in empty tabs. I refreshed Firefox and now I have a 'Old Firefox Data' folder. I have a sessionrestore-backups folder in that folder, with a 'previous.js' file. How do I use this file (or any of the others in the folder) to gain access to my lost session? Is it possible at all? Thanks for any and all help.

Chosen solution

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).

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Chosen Solution

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).

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Thank you. I managed to do so and now I can access my old Restore Session option.

But the glitch remains; as in, the Restore Session Error window shows all my active tabs, but if I click restore, it opens a new window with all empty tabs.

If it helps clarify the issue, I get at least two Unresponsive Script errors when Firefox tries to load these tabs. One relates to the tabbrowser and the other to content. These did not appear before the blackout.

Is there any way to resolve this issue?

Edit: I opened the previous.js file I was using to restore my session in Word and all the URLs are definitely there. So I am not sure why Firefox is only opening empty tabs.

Modified by DerekSands