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Restoring previous session after closing firefox.

  • 2 replies
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  • 3 views
  • Last reply by cor-el

sotini0504
sotini0504
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My computer needed to be updated so I click on update without closing any programs because the computer usually does it. At this time I was in the School Library well the update was completed so I open up Firefox usually when i open firefox after a shutdown or some other reason. I can go to Open Application Menu>History>RestorePreviousSession but before I clicked on Restore Previous Session I realize that I need to go to class, so I closed my computer. once in class I open my computer up and I try to restore my previous session but by the time that I tried to restore it my session was deleted and my question is if anyone at FIREFOX can help restore that deleted session because I was working on my research project which is due this week, and in that particular session I had tabs open that I need so i can finish my project. Please reach out as soon as possible. This happen on Tuesday. Thank You

My computer needed to be updated so I click on update without closing any programs because the computer usually does it. At this time I was in the School Library well the update was completed so I open up Firefox usually when i open firefox after a shutdown or some other reason. I can go to Open Application Menu>History>RestorePreviousSession but before I clicked on Restore Previous Session I realize that I need to go to class, so I closed my computer. once in class I open my computer up and I try to restore my previous session but by the time that I tried to restore it my session was deleted and my question is if anyone at FIREFOX can help restore that deleted session because I was working on my research project which is due this week, and in that particular session I had tabs open that I need so i can finish my project. Please reach out as soon as possible. This happen on Tuesday. Thank You

All Replies (2)

sotini0504
sotini0504 Question owner
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It's my computer.

cor-el
cor-el
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  • Top 10 Contributor
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The only way to restore a lost session is via an upgrade.jsonlz4 in the sessionstore-backups folder or by browsing a Windows System Restore point to see if you can locate an older copy on sessionstore.jsonlz4.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page (Root directory).

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.

You can look at a utility to browse System Restore points.