Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

The sessionstore-backup Directory

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

more options

I've just rebooted and I've lost two windows with thirty tabs, or something.

When I started Firefox, there's nothing in the Recently Closed [Tabs, Windows]

Reading online, I see that Firefox should be writing some files to the sessionstore-backup directory, like these:

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

, but I only find recovery.jsonlz4 and recovery.baklz4 and both are tracking current time, which means they are getting data from the currently opened Firefox.

These are the only files I find in this directory.

Where are the other files supposed to have gone?

I've just rebooted and I've lost two windows with thirty tabs, or something. When I started Firefox, there's nothing in the Recently Closed [Tabs, Windows] Reading online, I see that Firefox should be writing some files to the sessionstore-backup directory, like these: 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 , but I only find recovery.jsonlz4 and recovery.baklz4 and both are tracking current time, which means they are getting data from the currently opened Firefox. These are the only files I find in this directory. Where are the other files supposed to have gone?

All Replies (6)

more options

You may have switched to another profile.

You can check if you have an "Old Firefox Data" folder on the desktop in case the Refresh feature in Firefox has been used and a new profile has been created.

more options

I have not switched to another profile, because I only have a single profile:

~/.mozilla/firefox]$ ls -lh total 16K drwx------ 4 b0ef users 4.0K Sep 24 09:53 'Crash Reports' drwx------ 13 b0ef users 4.0K Sep 25 01:59 lovh1aa7.default drwx------ 2 b0ef users 4.0K Sep 20 14:06 'Pending Pings' -rw-r--r-- 1 b0ef users 114 Sep 20 14:06 profiles.ini

more options

If you are on Ubuntu then you may have switched to the Firefox Snap version and that version uses a different location for the profile folder.

  • ~/snap/firefox/common/.mozilla/firefox/xxxxxxxx.default

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).

See also:

more options

No, I'm on NixOS and I don't have Snap;)

more options

ok, so this must be a bug, then, if Firefox doesn't leave a previous.jsonlz4 in there.

Can you point to a reference in the source code, where this logic happens?

Also, if I create my own backups of the recovery* file, how can I export tabs from it and then import tabs into Firefox using the command line?

more options

previous.jsonlz4 is created when Firefox starts as a backup of the previous sessionstore.jsonlz4 to be able to restore the previous session later in the session, so if there isn't a sessionstore.jsonlz4 or you have restored the session then there also won't be a previous.jsonlz4.

If you do not have upgrade.jsonlz4-build_id files then it is likely that updates are handled by your Linux software management (i.e. isn't under control of Firefox).