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Lost tabs

  • 3 replies
  • 0 have this problem
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  • Last reply by cor-el

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Problem I had two versions of Firefox open. Window "A" (my primary window) had many open tabs. Window "B" had only three tabs open. Like a knucklehead I accidentally closed the wrong window, "A". Upon restarting only the "B" version was there.

Possible Solution Two days ago I cloned my "C" drive as a backup. Although the Profile folder on the backup will only have 90+% of the tabs - I can gratefully live with that. I just need to know what files to copy over from the backup drive Profile folder to the messed up drive's Profile folder. I am hoping it will be that easy and I can copy the tab files and not the entire Profile folder. Thanks.

Problem I had two versions of Firefox open. Window "A" (my primary window) had many open tabs. Window "B" had only three tabs open. Like a knucklehead I accidentally closed the wrong window, "A". Upon restarting only the "B" version was there. Possible Solution Two days ago I cloned my "C" drive as a backup. Although the Profile folder on the backup will only have 90+% of the tabs - I can gratefully live with that. I just need to know what files to copy over from the backup drive Profile folder to the messed up drive's Profile folder. I am hoping it will be that easy and I can copy the tab files and not the entire Profile folder. Thanks.

All Replies (3)

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Did you check "History -> Recently Closed Windows" ?

You can try to restore a recent upgrade.jsonlz4-<build_id> when available or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

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.

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I did check "History -> Recently Closed Windows" but all that was there was the lost tabs version of FF when I opened it.

I did not understand the differences and function between previous.jsonlz4, recovery.baklz4, recovery.jsonlz4, and upgrade.jsonlz4. So I compared those files with my backup of two days previously. upgrade.jsonlz4 had the same date/time/size but the other three had a date two days previous. so I overwrote them. I then looked at the root of my profile folder and sessionstore.bak and sessionstore.js had the same date/time/size so I left them alone. My idea did not work. When I booted up FF it was like a new install, only one tab open.

So next I overwrote the entire Profile folder with the profile folder from two days previous. PROBLEM SOLVED, there were all my tabs. Fortunately I had this recent backup of my "C" drive to rely on.

I am not a programmer so I assume there is some reason this works the way it does but it would sure be a lot simpler, and user friendly, if a problem like this could be remedied with a tabs backup file.

Thank you cor-el for responding to my post. Hopefully this will help someone in the future who has the same dilemma.

If I remember correctly, several years back, there was an add-on that could restore lost tabs with just a click and away you go. Am I mis-remembering this? My recollection is that not only did I have the add-on but I used it successfully more than once.

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You need to copy one of the sessionstore files in the sessionstore-backups folder to the parent level to replace the current sessionstore.jsonlz4 with Firefox closed to make Fire use this sessionstore file.