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Lost my most recent FF session. (FF restarted twice now). FF now open. Which session file do I copy, to try and correct older session restored?

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  • 1 has this problem
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  • Last reply by mnalep

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I Lost my FF session, (not sure what I did, but the menu toolbar shortcuts were gone & I cold not 'click' them back, so I figures I would just reboot FF.

Some dialog box popped up (I don't recall exactly what the box said, but offered me a choice to CANCEL or CONTINUE. I hit CONTINUE. FF Shut down, and when it reopened a couple of my FF windows were missing, but the toolbar shortcuts were restored.

So, I figured I would restart FF a 2nd time. Well, still missing a few windows. FF session still open.

I am looking at the session files, and trying to determine which session file do I copy, and to where, to try and get old session restored, if I can?

I tried loading the larger 58,175 KB file from 7/16/21, and it crashed the scrounger page.

I am loading a smaller in 56,853 KB file from 10/8/21 (today's date) into your SCROUNGER page, and it has been running for 10 minutes now.

I thought it might be simpler to just copy or rename the correct file (after backing them all up) into the file that will be used after I close, and restart my current FF session & just look and see what FF opens. I just don;t recall which file FF uses for each new startup. Is it recovery.jsonlz4? previous.jsonlz4? something else?

I've uploaded an image, of the screen capture, of a few of my most recently dated session files, in this folder:

C:\Users\matt\AppData\Roaming\Mozilla\Firefox\Profiles\jazvjrpa.default-1600876215262\sessionstore-backups

I Lost my FF session, (not sure what I did, but the menu toolbar shortcuts were gone & I cold not 'click' them back, so I figures I would just reboot FF. Some dialog box popped up (I don't recall exactly what the box said, but offered me a choice to CANCEL or CONTINUE. I hit CONTINUE. FF Shut down, and when it reopened a couple of my FF windows were missing, but the toolbar shortcuts were restored. So, I figured I would restart FF a 2nd time. Well, still missing a few windows. FF session still open. I am looking at the session files, and trying to determine which session file do I copy, and to where, to try and get old session restored, if I can? I tried loading the larger 58,175 KB file from 7/16/21, and it crashed the scrounger page. I am loading a smaller in 56,853 KB file from 10/8/21 (today's date) into your SCROUNGER page, and it has been running for 10 minutes now. I thought it might be simpler to just copy or rename the correct file (after backing them all up) into the file that will be used after I close, and restart my current FF session & just look and see what FF opens. I just don;t recall which file FF uses for each new startup. Is it recovery.jsonlz4? previous.jsonlz4? something else? I've uploaded an image, of the screen capture, of a few of my most recently dated session files, in this folder: C:\Users\matt\AppData\Roaming\Mozilla\Firefox\Profiles\jazvjrpa.default-1600876215262\sessionstore-backups
Attached screenshots

All Replies (7)

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Hey there!

Please have a look at the following link to see if it helps:

https://support.mozilla.org/en-US/kb/restore-previous-session

Hope I helped!

Kind regards,

Bithiah

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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 to restore the session saved in the file.

  • make sure to backup the current sessionstore.jsonlz4
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Hi Cor-el. I am a little confused about which folder you called the 'main profile' folder.

I have this folder, which I believe is what you mean is the 'session store backups' folder: C:\Users\matt\AppData\Roaming\Mozilla\Firefox\Profiles\jazvjrpa.default-1600876215262\sessionstore-backups

I don't see a sessionstore.jsonlz4 in any folder. But, I do see a file called sessionstore.jsonlz4.tmp, in: C:\Users\matt\AppData\Roaming\Mozilla\Firefox\Profiles\jazvjrpa.default-1600876215262

Is C:\Users\matt\AppData\Roaming\Mozilla\Firefox\Profiles\jazvjrpa.default-1600876215262 what you are referring to as the "main profile" folder? (and is the sessionstore.jsonlz4.tmp going to be the sessionstore.jsonlz4 - after I close FF?

I have created a new folder called "profile directory files on 10-8-21" , and copied everything from C:\Users\matt\AppData\Roaming\Mozilla\Firefox\Profiles\jazvjrpa.default-1600876215262\sessionstore-backups - into that folder, so I guess I have a backup copy of sessionstore.jsonlz4 in that folder, (which right now is the "sessionstore.jsonlz4.tmp" file since FF is still running ?

(Boy, this would be easier to talk about if these folder names were not so long and cumbersome, lol)

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I do not see a sessionstore.jsonlz4 file in my profile folder. (FF is closed) .

I only see a sessionstore.jsonlz4.old, and a sessionstore.jsonlz4.tmp.

Am i missing the sessionstore.jsonlz4 file?

I am having lot of trouble with FF freezing. ( I do have thousands of tabs open over 15 windows...and suddenly started seeing 100% DISK USAGE in my TASK MGR).

But, even with all those tabs it pretty much works ok actually. I just restart it when it gets slow.

I was thinking about restoring a sessionstore file that I backed up about two weeks ago, to see if that fixes the FF freezing issue that just started yesterday.

Below is a pic of the sessionstore files, that are currently in my profile folder:

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What files are in the sessionstore-backups folder ? Are the recovery.jsonlz4 and recovery.baklz4 being updated during the current session ?


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
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deleted ...

Modified by mnalep

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Oops. posted that question above ... twice.

Anyways, to answer your question about what is in sessionstore-backups. Yes, I ahve all the files you mentioned. and quite a few others. I don't know why though?

The current contents are in the pic I am attaching below.

It sounds like I should copy previous.jsonlz4 into the main profile as sessionstore.jsonlz4? And then start FF? (Is it normal that there is currently no sessionstore.jsonlz4 in my profile folder - since FF is currently closed?

Also, I just noticed that the sessionstore.jsonlz4.old, and the sessionstore.jsonlz4.tmp, in the regular profile folder (jazvjrpa.default-1600876215262 - were created on 10-12-21 and 10-14-21, respectively. I am trying to remember if those were files I copied, and created, about 12 days ago? Are those 'standard' FF files, or did I must have created them?)