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Closed tabs not restoring

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  • Last reply by cor-el

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Hello, I closed my browser, expecting it to save my current tabs as it usually does. When I reopened it, the tabs were gone. They were important for me, and some of them were pretty old so I can't find them in my history. I tried checking the "recently closed tabs" option, it didn't help. There was also no option to restore the previous session. Can you help me restore my lost tabs?

Hello, I closed my browser, expecting it to save my current tabs as it usually does. When I reopened it, the tabs were gone. They were important for me, and some of them were pretty old so I can't find them in my history. I tried checking the "recently closed tabs" option, it didn't help. There was also no option to restore the previous session. Can you help me restore my lost tabs?

Chosen solution

Were those tab the only data you lost?

You can check if you have an upgrade.jsonlz4 with those lost tabs.

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 try to restore the upgrade.jsonlz4 file from the last update or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

You can copy a file with Firefox closed from the sessionstore-backups folder to the main profile folder and rename the file to sessionstore.jsonlz4 to replace the current file.

  • make sure to backup the current sessionstore.jsonlz4

You can look at this tool to inspect a compressed jsonlz4 sessionstore file. This tool works locally, no uploading done.

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Chosen Solution

Were those tab the only data you lost?

You can check if you have an upgrade.jsonlz4 with those lost tabs.

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 try to restore the upgrade.jsonlz4 file from the last update or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

You can copy a file with Firefox closed from the sessionstore-backups folder to the main profile folder and rename the file to sessionstore.jsonlz4 to replace the current file.

  • make sure to backup the current sessionstore.jsonlz4

You can look at this tool to inspect a compressed jsonlz4 sessionstore file. This tool works locally, no uploading done.