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Firefox Destroyed Session Restore

  • 4 uphendule
  • 1 inale nkinga
  • 312 views
  • Igcine ukuphendulwa ngu pamelap1

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Firefox (97.0 64 bit, windows 10) destroyed all my previous tabs (4 windows lots of tabs) when I opened it despite always having "Firefox will" set to "Remember History". It just opened one window with the Home page.

Trying to sort it out using restore all tabs and then all windows, it just made the problem worse and the restored tabs eventually stopped restoring so now I have useless json files.

The files I have in my profile are:

previous.jsonlz4 15/2/2022 18:46 recovery.baklz4 15/2/2022 19:10 recovery.jsonlz4 15/2/2022 19:10 (this file changes its name from bak to json and back to bak again, very odd) upgrade.jsonlz4-20220119190439 26/1/2022 00:23 upgrade.jsonlz4-20220126154723 29/1/2022 04:31 upgrade.jsonlz4-20220202182137 12/2/2022 17:40

Is it possible "previous.jsonlz4" may have all the windows and tabs that I lost?

If so, how could I get Firefox to use it when I next open it? (assuming if I close this browser it won't overwrite the "previous.jsonlz4" file??).

Also could I use the upgrade.jsonlz4 file to try to restore all the windows and tabs that I lost? The windows would have been much the same on 12 Feb as they were today before the destruction.

Firefox (97.0 64 bit, windows 10) destroyed all my previous tabs (4 windows lots of tabs) when I opened it despite always having "Firefox will" set to "Remember History". It just opened one window with the Home page. Trying to sort it out using restore all tabs and then all windows, it just made the problem worse and the restored tabs eventually stopped restoring so now I have useless json files. The files I have in my profile are: previous.jsonlz4 15/2/2022 18:46 recovery.baklz4 15/2/2022 19:10 recovery.jsonlz4 15/2/2022 19:10 (this file changes its name from bak to json and back to bak again, very odd) upgrade.jsonlz4-20220119190439 26/1/2022 00:23 upgrade.jsonlz4-20220126154723 29/1/2022 04:31 upgrade.jsonlz4-20220202182137 12/2/2022 17:40 Is it possible "previous.jsonlz4" may have all the windows and tabs that I lost? If so, how could I get Firefox to use it when I next open it? (assuming if I close this browser it won't overwrite the "previous.jsonlz4" file??). Also could I use the upgrade.jsonlz4 file to try to restore all the windows and tabs that I lost? The windows would have been much the same on 12 Feb as they were today before the destruction.

Isisombululo esikhethiwe

Hopefully you saved a backup copy of those files to preserve them -- as you noted, Firefox regularly updates them.

I have a tool to generate a list of the tabs in a session history file. You can drag and drop it onto the box and after Firefox extracts its contents, click "Scrounge URLs" to generate the list. You can use the Save List button to archive it as a locally saved HTML file in case other methods of recovery are not successful, or in case you don't actually need all of those tabs at once.

https://www.jeffersonscher.com/ffu/scrounger.html

Note: If the script doesn't give you a list within 15 seconds, the tab probably crashed. You can close the tab and try again in a new tab.


After identifying the file that makes the most sense to restore, we can suggest how to swap it with the file Firefox will look for at startup. More or less the following, but be sure to keep backups of the files you drop in since Firefox may discard them:

(1) Open your profile folder in Windows File Explorer

(2) Exit Firefox and wait for it to create the sessionstore.jsonlz4 file and update the sessionCheckpoints.json file

(3) Hide those two files by renaming:

  • right-click sessionstore.jsonlz4 => Rename sessionstoreOLD.jsonlz4
  • right-click sessionCheckpoints.json => Rename sessionCheckpointsOLD.json

(4) Hide the sessionstore-backups folder

  • right-click sessionstore-backups => Rename sessionstore-backupsOLD

(5) Drop in the file you want to substitute and rename. For example:

  • right-click previous.jsonlz4 => Rename sessionstore.jsonlz4

At the next startup, Firefox should load that file, or it should be available under Restore Previous Session.

Success?

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All Replies (4)

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Isisombululo Esikhethiwe

Hopefully you saved a backup copy of those files to preserve them -- as you noted, Firefox regularly updates them.

I have a tool to generate a list of the tabs in a session history file. You can drag and drop it onto the box and after Firefox extracts its contents, click "Scrounge URLs" to generate the list. You can use the Save List button to archive it as a locally saved HTML file in case other methods of recovery are not successful, or in case you don't actually need all of those tabs at once.

https://www.jeffersonscher.com/ffu/scrounger.html

Note: If the script doesn't give you a list within 15 seconds, the tab probably crashed. You can close the tab and try again in a new tab.


After identifying the file that makes the most sense to restore, we can suggest how to swap it with the file Firefox will look for at startup. More or less the following, but be sure to keep backups of the files you drop in since Firefox may discard them:

(1) Open your profile folder in Windows File Explorer

(2) Exit Firefox and wait for it to create the sessionstore.jsonlz4 file and update the sessionCheckpoints.json file

(3) Hide those two files by renaming:

  • right-click sessionstore.jsonlz4 => Rename sessionstoreOLD.jsonlz4
  • right-click sessionCheckpoints.json => Rename sessionCheckpointsOLD.json

(4) Hide the sessionstore-backups folder

  • right-click sessionstore-backups => Rename sessionstore-backupsOLD

(5) Drop in the file you want to substitute and rename. For example:

  • right-click previous.jsonlz4 => Rename sessionstore.jsonlz4

At the next startup, Firefox should load that file, or it should be available under Restore Previous Session.

Success?

Helpful?

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I found your website jscher2000 and used it to manually open the old tabs. Luckily there were some tabs found that were older, not all but most.

However, there are no files in my profile for sessionstore.jsonlz4 - the only sessionstore is the backups folder. I think this is due to a change in Firefox, I am using the latest version 97.0.

Helpful?

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pamelap1 said

However, there are no files in my profile for sessionstore.jsonlz4 - the only sessionstore is the backups folder. I think this is due to a change in Firefox, I am using the latest version 97.0.

That's normal because the file only exists while Firefox is closed. When it opens, Firefox removes the file and uses its contents to create the recovery.jsonlz4 file (if you restore your session automatically) or the previous.jsonlz4 file (if you do not).

Of course, if there was also a change in Firefox 97, I might have missed it due to some other big issues.

Helpful?

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Thanks! And yes, I did save a copy of the session restore files.

Helpful?

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