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In Firefox, after a reboot, how can I re-open my previous sessions?

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  • Last reply by NoahSUMO

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In Firefox, after a reboot, how can I re-open my previous sessions?

Originally I had quite a lot of open browsers & tabs. Then I needed to do a reboot, and now I've lost those previous sessions.

Usually I just open Firefox, and this opens one browser, and then all of my previous browser, and tabs reopen, but this time Firefox crashed, and its popup said it needed to restart, but it would re-open my previous browser and tabs, but it didn't.

After following the usual Firefox help guides, it still wouldn't re-open my previous sessions. Now if I ask it to open my previous sessions, it just opens the recent help guides, and not anything before the crash.

So is there a backup file of my missing sessions that I can roll back to?

In Firefox, after a reboot, how can I re-open my previous sessions? Originally I had quite a lot of open browsers & tabs. Then I needed to do a reboot, and now I've lost those previous sessions. Usually I just open Firefox, and this opens one browser, and then all of my previous browser, and tabs reopen, but this time Firefox crashed, and its popup said it needed to restart, but it would re-open my previous browser and tabs, but it didn't. After following the usual Firefox help guides, it still wouldn't re-open my previous sessions. Now if I ask it to open my previous sessions, it just opens the recent help guides, and not anything before the crash. So is there a backup file of my missing sessions that I can roll back to?

Modified by NoahSUMO

All Replies (6)

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Anyone Have Any Idea's ?? Many Thanks

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Yes, the session issue is a problem in Firefox, but here is a detailed answer. https://support.mozilla.org/en-US/questions/1449521

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The most critical advice is that you need to back up your sessionrestore files. Please do this before opening Firefox too many times. As doing that, will overwrite the backup files & lose your tabs.

To find your Firefox profile without opening Firefox: https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data#w_finding-your-profile-without-opening-firefox

Then focus on backing up the sessionstore-backups folder. You can also backup the entire Firefox profile if you want by copying it to another location.

Tab backup steps I copied from Cor-el's post: In your Firefox profile folder, double-click into the sessionstore-backups folder. Save all files here to a safe location such as your Documents folder.

What files did you find? The kinds of files you may find among your sessionstore files are:

  • recovery.jsonlz4: the windows and tabs in your currently live Firefox session (or, if Firefox crashed at the last shutdown and is still closed, your last session)
  • recovery.baklz4: a backup copy of recovery.jsonlz4
  • previous.jsonlz4: the windows and tabs in your last Firefox session
  • upgrade.jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update
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You can look at this tool to inspect a compressed jsonlz4 sessionstore file to check if a sessionstore file has your lost tabs. This tool works locally, no uploading done.

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NoahSUMO said

The most critical advice is that you need to back up your sessionrestore files. Please do this before opening Firefox too many times. As doing that, will overwrite the backup files & lose your tabs. Then focus on backing up the sessionstore-backups folder. You can also backup the entire Firefox profile if you want by copying it to another location.

Yeah, I started doing this months ago when I noticed in Nightly that the contents of the sessionstore-backups folder was being erased. see screenshot I assume the devs are aware of this because I did mention it on the https://chat.mozilla.org/#/room/#nightly:mozilla.org They also created a new folder in Nightly for logs. see screenshot

Modified by jonzn4SUSE

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Oh awesome. Nice find! I had no idea they started logging the success rate of the sessionrestore files. My idea for the devs was to ask them to create more session backups over a longer period of time. In case one of the session restore files ends up becoming corrupted. Maybe 1 week worth of backups. But since we get users who've been late to report they lost their tabs, I think 2 weeks worth of backups would be really nice.

I will file that bug soon. I hope they are open to implementing it.