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Clearing history removes session tabs when I close FF - no warning!

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  • 1 has this problem
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  • Last reply by cor-el

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Clearing history removes session tabs and pinned sites when I close FF - and there is NO warning!

What is interesting is that I only asked FF to clear 4 hours of history, and these tabs have been opened for weeks.

I do not recall many of those sites as I kept them open as part of my workflow.

Clearing history removes session tabs and pinned sites when I close FF - and there is NO warning! What is interesting is that I only asked FF to clear 4 hours of history, and these tabs have been opened for weeks. I do not recall many of those sites as I kept them open as part of my workflow.

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Open tabs (session history) is considered to be part of the browsing history, so if you use "Clear history when Firefox closes" to clear the browsing history then you will lose open tabs with no way to recover unless you didn't clear the cache and pages you visited recently are still in the cache.

You may have a upgrade.jsonlz4-<build_id> file in the sessionstore-backups folder in the profile folder from the last update, but this is likely not a recent backup (Firefox 69 is due to be released next week).


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 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 these utilities to browse System Restore points.