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Can I restore previous groups of tabs after accidentally opening a new session?

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  • Last reply by bmaser

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I had about 8 groups of 6 tabs each, open all the time. After a recent Windows update, I accidentally opened Firefox without restoring the previous session. Now I seem to have lost all those groups - do I have to re-create them all one at a time? If so, is there a way to backup the groups so this doesn't happen again?

I had about 8 groups of 6 tabs each, open all the time. After a recent Windows update, I accidentally opened Firefox without restoring the previous session. Now I seem to have lost all those groups - do I have to re-create them all one at a time? If so, is there a way to backup the groups so this doesn't happen again?

Chosen solution

Do you have a upgrade.js-<build_id> file that might have those tab groups?

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

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/

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Chosen Solution

Do you have a upgrade.js-<build_id> file that might have those tab groups?

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

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/

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Wonderful - that did the trick. Thanks!