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Where is the previous session file in Firefox Quantum? Information on Firefox forum seems outdated about location and filename of previous session.

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  • Last reply by user1929

Pablo_Lascano
Pablo_Lascano
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Hi, I updated to Quantum (actually Firefox did it on its own), and since then the addon "session-manager" is no longer working.

Until now I have been able to deal with the situation by always restoring the old session, until Firefox updated and by some unlucky chance it exited before I could restore my session.

When I restored, it was only an empty session. I already identified the file I want to restore, which is in the \sessionstore-backups\ , and its name is upgrade.jsonlz4-20171128222554 , about 800 KB, and contains all the tabs I want.

How do I rename the file and where should I copy it so that when I hit "restore previous session" it loads THAT FILE instead. I have tried renaming it to previous.js or restore.js, and copying it into the main directory, but it doesn't load it. The information I found on the Firefox forum seems outdated since I could not find the filenames they are talking about and I suspect this is due to the new version of Firefox, Quantum.

Thank you in advance, regards,

P. J. L.

Hi, I updated to Quantum (actually Firefox did it on its own), and since then the addon "session-manager" is no longer working. Until now I have been able to deal with the situation by always restoring the old session, until Firefox updated and by some unlucky chance it exited before I could restore my session. When I restored, it was only an empty session. I already identified the file I want to restore, which is in the \sessionstore-backups\ , and its name is upgrade.jsonlz4-20171128222554 , about 800 KB, and contains all the tabs I want. How do I rename the file and where should I copy it so that when I hit "restore previous session" it loads THAT FILE instead. I have tried renaming it to previous.js or restore.js, and copying it into the main directory, but it doesn't load it. The information I found on the Firefox forum seems outdated since I could not find the filenames they are talking about and I suspect this is due to the new version of Firefox, Quantum. Thank you in advance, regards, P. J. L.

Chosen solution

It looks like the correct filename for Firefox 56+ is sessionstore.jsonlz4 (based on https://hg.mozilla.org/mozilla-central/rev/733cfc278628#l1.12 ). This file should be located in the main directory of your profile.

(Before doing this, it's a good idea to make a backup of your profile folder in case something goes wrong).

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user1929
user1929
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Chosen Solution

It looks like the correct filename for Firefox 56+ is sessionstore.jsonlz4 (based on https://hg.mozilla.org/mozilla-central/rev/733cfc278628#l1.12 ). This file should be located in the main directory of your profile.

(Before doing this, it's a good idea to make a backup of your profile folder in case something goes wrong).