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I've lost over 30 tabs due to crashes, my sync data overrided already, how can I restore an old sync session or find the data/restore those tabs?

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  • Last reply by cor-el

raijha
raijha
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MY PC restarted twice in a row and somehow that caused Firefox to lose all my tabs, including pinned (for the second time.) NONE of the restore session settings in the browser are available and while I was in the process of manually restoring the tabs using the sync data from my phone, without touching anything, it removed all my data. Reset my sync actually back to 0 devices. Please, please, please tell me there's a cache or way I can find some old sync data so I don't have to try and remember my 30+ tabs of information again.

MY PC restarted twice in a row and somehow that caused Firefox to lose all my tabs, including pinned (for the second time.) NONE of the restore session settings in the browser are available and while I was in the process of manually restoring the tabs using the sync data from my phone, without touching anything, it removed all my data. Reset my sync actually back to 0 devices. Please, please, please tell me there's a cache or way I can find some old sync data so I don't have to try and remember my 30+ tabs of information again.

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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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. Do NOT close Firefox when Firefox is already running.

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

  • previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
  • recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
  • recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
  • upgrade.jsonlz4-<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.jsonlz4 to replace the current file (make sure to backup the current sessionstore.jsonlz4).

You can try to restore a recent upgrade.jsonlz4-<build_id> when available or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

You can look at this utility to browse System Restore points.