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Session and and other settings were not imported upon migration

  • 4 replies
  • 1 has this problem
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  • Last reply by supercain3

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Hi,

My Windows just crashed and I had to perform a fresh install but before that I backed up my C:\Users\USER\AppData\Roaming\Mozilla\Firefox\ folder and then I installed Firefox in the newly installed Windows and pasted the contents from the backup onto the same location. My passwords, history and bookmarks are there but not so my last session and toolbar customizations. The highlight sites tab is also messed up. Why did it happen?

Thank you.

Hi, My Windows just crashed and I had to perform a fresh install but before that I backed up my C:\Users\USER\AppData\Roaming\Mozilla\Firefox\ folder and then I installed Firefox in the newly installed Windows and pasted the contents from the backup onto the same location. My passwords, history and bookmarks are there but not so my last session and toolbar customizations. The highlight sites tab is also messed up. Why did it happen? Thank you.

Chosen solution

Was Firefox running when the Windows crash occurred ?

If that is the case then some file in the profile folder might be corrupted.

Did you check the files in the sessionstore-backups folder ?

Backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data. Do NOT close Firefox when Firefox is already running.

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 (make sure to backup the current sessionstore.jsonlz4).

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

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Chosen Solution

Was Firefox running when the Windows crash occurred ?

If that is the case then some file in the profile folder might be corrupted.

Did you check the files in the sessionstore-backups folder ?

Backup the session files in the sessionstore-backups folder in the Firefox Profile Folder to make sure not to lose possible important session data. Do NOT close Firefox when Firefox is already running.

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 (make sure to backup the current sessionstore.jsonlz4).

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

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Thank you. That solved my session problem. But how about my top sites tab? I had many saved sites there and now it shows only a few ones. Where is that data stored?

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Is that about the tiles on the Firefox Home page ?

If you have pinned websites to tiles then this data is stored in a pref and saved in prefs.js. Changes made manually on the about:newtab page are stored in prefs that you can find on the about:config page.

  • browser.newtabpage.pinned => websites pinned to a tile
  • browser.newtabpage.blocked => websites removed by clicking the X (Dismiss) button in a tile

Note that it usually best not to copy/restore prefs.js, but redo settings in Options/Preferences and only copy specific prefs you want to keep to the current user.js. The prefs.js stores a lot of data that is used internally.

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I searched my backup files for pref.js but I only could find pref.js.bak which seems to be pretty old. Anyway, I replaced the new one with that and it didnt work. My pinned websites are still not there. So I put the new file back but now the icons on my toolbar are gone. What happened?

Thank you.