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Previous Session disappeared and I can't seem to restore it

  • 3 replies
  • 1 has this problem
  • 1348 views
  • Last reply by cor-el

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Hello, I didn't open Firefox from the 8th, I closed it normally as I always do with no worries since Firefox always launches with all my tabs+bookmarks saved and never remove cronology by itself. Guess updating must have done something, so I've read on the net and then here about some probable solutions, did find some files like recovery.jsonlz4 and .baklz4 along previous.jsonlz4 and sessionstore.jsonlz4 and saved them up in another folder, putting them back in the profile I've had on Firefox, but that didn't seem to have helped at all, Firefox still launches with nothing on and I don't know what to do anymore, so I've registered to ask for support here. Thanks.

Hello, I didn't open Firefox from the 8th, I closed it normally as I always do with no worries since Firefox always launches with all my tabs+bookmarks saved and never remove cronology by itself. Guess updating must have done something, so I've read on the net and then here about some probable solutions, did find some files like recovery.jsonlz4 and .baklz4 along previous.jsonlz4 and sessionstore.jsonlz4 and saved them up in another folder, putting them back in the profile I've had on Firefox, but that didn't seem to have helped at all, Firefox still launches with nothing on and I don't know what to do anymore, so I've registered to ask for support here. Thanks.

Chosen solution

You can look at this tool to inspect a compressed sessionstore file to see whether one of the files you saved has your lost session.

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 a utility to browse System Restore points to see if you can locate and older version of sessionstore.jsonlz4.


You can check for problems with the sessionstore.jsonlz4 file in the Firefox profile folder that stores session data.

  • rename/remove sessionstore.jsonlz4 and sessionstore.js

You may also have to rename the sessionstore-backups folder.

When sessionstore.jsonlz4 is deleted you lose pinned-tabs and open tabs and you will have to recreate them, so if necessary make a note or bookmark them. sessionstore.jsonlz4 is only present in the Firefox profile folder when Firefox is closed.

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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Chosen Solution

You can look at this tool to inspect a compressed sessionstore file to see whether one of the files you saved has your lost session.

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 a utility to browse System Restore points to see if you can locate and older version of sessionstore.jsonlz4.


You can check for problems with the sessionstore.jsonlz4 file in the Firefox profile folder that stores session data.

  • rename/remove sessionstore.jsonlz4 and sessionstore.js

You may also have to rename the sessionstore-backups folder.

When sessionstore.jsonlz4 is deleted you lose pinned-tabs and open tabs and you will have to recreate them, so if necessary make a note or bookmark them. sessionstore.jsonlz4 is only present in the Firefox profile folder when Firefox is closed.

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 ha detto

You can look at this tool to inspect a compressed sessionstore file to see whether one of the files you saved has your lost session. 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 a utility to browse System Restore points to see if you can locate and older version of sessionstore.jsonlz4.

You can check for problems with the sessionstore.jsonlz4 file in the Firefox profile folder that stores session data.

  • rename/remove sessionstore.jsonlz4 and sessionstore.js

You may also have to rename the sessionstore-backups folder.

When sessionstore.jsonlz4 is deleted you lose pinned-tabs and open tabs and you will have to recreate them, so if necessary make a note or bookmark them. sessionstore.jsonlz4 is only present in the Firefox profile folder when Firefox is closed.

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.

Used ShadowExplorer and searched the last restore point, found the old profile along the folders for bookmarks+session in their old location and restored them in the actual folder of Firefox new profile, the session was restored to the last backup which was exactly on the 08th (last time I did use Firefox with no issues) and simply had to import the bookmarks (saved them after the session files), thus restoring fully both my session and all the 100+ bookmarks I had saved! Thanks a bunch, this totally helped&saved me! :)

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You're welcome.