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Restore a Previous Session That Has Vanished

  • 1 reply
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  • Last reply by cor-el

tatterand
tatterand
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How do I get back a previous session of Firefox (windows)? Firefox froze up. I restarted my computer. Now my session in Firefox doesn't show up at all in 'History'. Isn't there a way to recover a previous session?? I've never had this issue before and had a lot of important tabs in that session that would take many hours to try and find in my complete history from all links.....

How do I get back a previous session of Firefox (windows)? Firefox froze up. I restarted my computer. Now my session in Firefox doesn't show up at all in 'History'. Isn't there a way to recover a previous session?? I've never had this issue before and had a lot of important tabs in that session that would take many hours to try and find in my complete history from all links.....

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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 look at this tool to inspect a compressed jsonlz4 sessionstore file. This tool works locally, no uploading done.