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Firefox Sync'd setting caused lost session

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Hi,

I had logged onto my Firefox sync account and shutdown my computer with "clear Firefox history on close" activated and can't recover my session even looking through my profiles folder for .jsonlz4 files.

Does this just clear my local history or is the sync'd history irrecoverable? (It seems like it is)

I've tried using window's file recovery tool to scan for the deleted files on my SSD but after reviewing the files with a hex editor, a huge top portion was zero'd out. Is this to do with TRIM or the data recovery tool just not picking up the right sectors?

Hi, I had logged onto my Firefox sync account and shutdown my computer with "clear Firefox history on close" activated and can't recover my session even looking through my profiles folder for .jsonlz4 files. Does this just clear my local history or is the sync'd history irrecoverable? (It seems like it is) I've tried using window's file recovery tool to scan for the deleted files on my SSD but after reviewing the files with a hex editor, a huge top portion was zero'd out. Is this to do with TRIM or the data recovery tool just not picking up the right sectors?

Ŋuɖoɖo si wotia

Were you using "Clear history when Firefox closes" to clear the browsing history as that will prevent session restore from restoring the previous session ?


You can check if you can find a recent upgrade.jsonlz4 in the sessionstore-backups folder in the profile folder.

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 with Firefox closed.

  • make sure to backup the current sessionstore.jsonlz4

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.

Xle ŋuɖoɖo sia le goya me 👍 0

All Replies (2)

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Ɖɔɖɔɖo si wotia

Were you using "Clear history when Firefox closes" to clear the browsing history as that will prevent session restore from restoring the previous session ?


You can check if you can find a recent upgrade.jsonlz4 in the sessionstore-backups folder in the profile folder.

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 with Firefox closed.

  • make sure to backup the current sessionstore.jsonlz4

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.

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cor-el said

Were you using "Clear history when Firefox closes" to clear the browsing history as that will prevent session restore from restoring the previous session ?

You can check if you can find a recent upgrade.jsonlz4 in the sessionstore-backups folder in the profile folder.

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 with Firefox closed.

  • make sure to backup the current sessionstore.jsonlz4

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.

The sessionstore-backups folder didn't have any relevant backups, could you tell me the behavior of these files? I'm not sure how they get deleted