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Lost abilty to restore tabs/history

  • 6 ŋuɖoɖowo
  • 1 masɔmasɔ sia le esi
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  • Nuɖoɖo mlɔetɔ phtcac

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One of my tabs split off from the bar leaving me two versions of Firefox open. I accidentally closed the main page with all the many tabs first and thus the single tab page was closed last which means the command to restore or open all the tabs doesn't work. You have the choice on the Firefox set up to Open the pages that were open when you closed. Unfortunately is there are what appear to be 2 Firefox browsers open if the unwanted one is closed last -- all the tabs from the other one do not restore and I can't find them in any kind of history.

Is there anyway to find/restore these tabs? Many were open and some of those to remind me of things I can't now remember were there, so I cannot find the information.

Thank you for ANY help with this.

One of my tabs split off from the bar leaving me two versions of Firefox open. I accidentally closed the main page with all the many tabs first and thus the single tab page was closed last which means the command to restore or open all the tabs doesn't work. You have the choice on the Firefox set up to Open the pages that were open when you closed. Unfortunately is there are what appear to be 2 Firefox browsers open if the unwanted one is closed last -- all the tabs from the other one do not restore and I can't find them in any kind of history. Is there anyway to find/restore these tabs? Many were open and some of those to remind me of things I can't now remember were there, so I cannot find the information. Thank you for ANY help with this.

All Replies (6)

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Is the other window in History > Recently Closed Windows?

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Note that best is to use one of these to close Firefox if you are currently doing that by clicking the close X on the Firefox Title bar, especially if you have multiple windows open to prevent losing tabs in unnoticed windows.

  • "3-bar" menu button -> Exit (Power button)
  • Windows: File -> Exit
  • Mac: Firefox -> Quit Firefox
  • Linux: File -> Quit

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 try to restore a recent upgrade.jsonlz4-<build_id> when available or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

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 sessionstore.jsonlz4 file with Firefox closed.

  • make sure to backup the current sessionstore.jsonlz4
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I know how to avoid the problem--just a loss in concentration and being in a hurry. I could possibly try your suggestion although probably too much time has passed. I cannot find a profile folder or any sessionstore folders or files. Searching does not help.

Thank you.

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FYI, there is a preference which you can set to false. browser.tabs.allowTabDetach

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Note that you can drag a tab you accidentally detached to another window back to the Tab bar in the original window.

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Thank you all for your attempts at support. I appreciate the basic information about tabs, etc but none of it answer my question about being able to restore those lost ones. The following suggestion might have helped but I couldn't find these files or folders or whatever they are: 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 try to restore a recent upgrade.jsonlz4-<build_id> when available or use a utility to browse Windows System Restore points to see if you can find a recent sessionstore.jsonlz4 file.

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 sessionstore.jsonlz4 file with Firefox closed.

   make sure to backup the current sessionstore.jsonlz4 

So I don't think this can now be accomplished. I appreciate the insights.