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

Lost previous session with Firefox 57 Quantum

more options

I had a bunch of important tabs open from a previous season and seemed to have lost the ability to restore the season with the new version. the restore previous season under the History menu is grayed out.

Please tell me how to restore my previous season before the upgrade.

I need an answer ASAP.

I had a bunch of important tabs open from a previous season and seemed to have lost the ability to restore the season with the new version. the restore previous season under the History menu is grayed out. Please tell me how to restore my previous season before the upgrade. I need an answer ASAP.

Modified by Soren Pearson

All Replies (13)

more options

Hello, you can restore your previous session after the update by clicking restart Firefox to Update, and it should automatically restore your previous session!

more options

Mkll said

Hello, you can restore your previous session after the update by clicking restart Firefox to Update, and it should automatically restore your previous session!

When I opened Firefox on my Mac for the first time, it opened and updated automatically but the restore previous session is grayed out.

Modified by Soren Pearson

more options

Oh, this only seems to have worked on Windows. My apologies, you can check your recent history, and you can open it manually from there.

more options

Mkll said

Oh, this only seems to have worked on Windows. My apologies, you can check your recent history, and you can open it manually from there.

Oh jeez, I wonder why this happened? I had a lot of stuff open so going though my history will take a while, something I don't want to do.

So I tried it, closed Firefox and reopened it again and it just restores the tab from the new version saying "The new Firefox. Fast for good. Today we’re thrilled to introduce you to our brand new browser — Firefox Quantum."

WTF?

if I wanted to restore from previous session, any chance I could roll back to a previous version or is it lost for ever? It better not be lost for ever as I lost important work.

Modified by Soren Pearson

more options

This is why we make backups my friend! Open your recent history pane and manually restore from that.

more options

Mkll said

This is why we make backups my friend! Open your recent history pane and manually restore from that.

Right, but how was I supposed to know this was going to happen? There was no way to make a back up as it automatically opened with the new version.

Also, it's going to take forever to try to go from History as somehow it never saves the restore from previous season, just the new tabs or windows I open. Trying to remember will take ages.

So i've lot everything right?

Mozilla should automatically backup the previous version and data before upgrading as this is one hot mess.

Modified by Soren Pearson

more options

Sorry to hear about this problem. Could you start off by backing up the session files you have right now? Here's how:

You can open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter/Return

In the first table on the page, next to Profile Folder, click the "Open in Finder" button (on Windows, "Open Folder" to show in Windows Explorer).

In your profile folder, scroll down and double-click into the sessionstore-backups folder. Save all files here to a safe location, such as your Desktop or Documents folder. If not too much time has passed, we may be able to use them to recover your lost tabs.

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

  • recovery.js, 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.bak, recovery.baklz4: a backup copy of recovery.js
  • previous.js, previous.jsonlz4: the windows and tabs in your last Firefox session
  • upgrade.js/jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update

Could you take a look at what you have and the date/time of the various files to see whether you think any of them would have the missing tabs?

To view the contents of a session history file, you can drag and drop it onto this tool: https://www.jeffersonscher.com/res/scrounger.html (that's on my website, so if it doesn't work, let me know).

more options

I looked in my profiles folder and see a folder that says sessionstore-backups and a file sessionstore.js If I reverted to the previous version, would I have any luck restoring from those files?

Please help as I'm desperate here.

more options

jscher2000 said

Sorry to hear about this problem. Could you start off by backing up the session files you have right now? Here's how: You can open your current Firefox settings (AKA Firefox profile) folder using either
  • "3-bar" menu button > "?" button > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter/Return
In the first table on the page, next to Profile Folder, click the "Open in Finder" button (on Windows, "Open Folder" to show in Windows Explorer). In your profile folder, scroll down and double-click into the sessionstore-backups folder. Save all files here to a safe location, such as your Desktop or Documents folder. If not too much time has passed, we may be able to use them to recover your lost tabs. The kinds of files you may find among your sessionstore files are:
  • recovery.js, 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.bak, recovery.baklz4: a backup copy of recovery.js
  • previous.js, previous.jsonlz4: the windows and tabs in your last Firefox session
  • upgrade.js/jsonlz4-build_id: the windows and tabs in the Firefox session that was live at the time of your last update
Could you take a look at what you have and the date/time of the various files to see whether you think any of them would have the missing tabs? To view the contents of a session history file, you can drag and drop it onto this tool: https://www.jeffersonscher.com/res/scrounger.html (that's on my website, so if it doesn't work, let me know).

Thanks, I opened up one of the files dated October 27 and can see a list of tabs and such not everything but most of them using your website, would I replace the current file with this file and I should be good to go?

Please advise.

more options

Yep, that should do it!

more options

Soren Pearson said

Thanks, I opened up one of the files dated October 27 and can see a list of tabs and such not everything but most of them using your website, would I replace the current file with this file and I should be good to go?

So when Firefox shuts down normally, it removes the recovery.jsonlz4, recovery.baklz4, and creates a file named sessionstore.jsonlz4 in the main level of the profile folder. That's the file you want to replace. So:

(A) Exit Firefox (B) Rename sessionstore.jsonlz4 to sessionstore-old.jsonlz4 (C) Copy in the file you want Firefox to restore at startup (D) Rename that file to sessionstore.jsonlz4 (E) Start Firefox

If you normally have your previous session restored automatically, that should happen, or you can use History > Restore Previous Session

Success?

more options

jscher2000 said

Soren Pearson said
Thanks, I opened up one of the files dated October 27 and can see a list of tabs and such not everything but most of them using your website, would I replace the current file with this file and I should be good to go?

So when Firefox shuts down normally, it removes the recovery.jsonlz4, recovery.baklz4, and creates a file named sessionstore.jsonlz4 in the main level of the profile folder. That's the file you want to replace. So:

(A) Exit Firefox (B) Rename sessionstore.jsonlz4 to sessionstore-old.jsonlz4 (C) Copy in the file you want Firefox to restore at startup (D) Rename that file to sessionstore.jsonlz4 (E) Start Firefox

If you normally have your previous session restored automatically, that should happen, or you can use History > Restore Previous Session

Success?

Yes, I got some of the tabs back. Now that I look back, it seems that it was meant to happen that the previous session disappeared, sometimes it's good to start with a clean slate. :-)

more options

Maybe fate intervened?

Did you notice whether the installer created a fresh upgrade.jsonlz4-buildid file? I would have thought that would be the latest, but perhaps there was a glitch in that process which caused this problem.