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previous.jsonlz4 & recovery.baklz4 files in sessionstore-backups

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  • Last reply by cor-el

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Can I change how often the previous.jsonlz4 & recovery.baklz4 files update? I'd like it if those files updated themselves every 5 minutes if possible.

Can I change how often the previous.jsonlz4 & recovery.baklz4 files update? I'd like it if those files updated themselves every 5 minutes if possible.

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previous.jsonlz4 is never updated during the current session as this is a copy of sessionstore.jsonlz4 from when Firefox was last started (i.e. files restored when you opened this session). The recovery files will/should be updated when you make changes to open tabs although there might be a delay if you make many changes in a short time.

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