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Remote Tech Chat Window left open, main window with 1200 synced tabs closed, need synced tabs back

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  • Last reply by Johnny

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A remote tech was logged in to my machine and had a chat window (Firefox window) opened. My main Firefox window was also opened as it always is. My main firefox window had approximately 1200 tabs that were synced and have been opening when I open firefox for more than a year. Most of these tabs were very important. Well the main Firefox window was closed with the secondary chat window still opened. Just like that, my massively important 1200 synced tabs were gone!!! Can someone please tell me how to recover them. The tech did open a few blank tabs once i pointed out what had been done. How can I recover all of those tabs?

Secondly, can a synced tab session be saved (or backed up) as you used to be able to do in the early days of tabs / session manager?

And finally, I need to have my internal drive replaced, is there some way that I can save my open / synced tabs for restoring on new drive after windows reload? Thank you

A remote tech was logged in to my machine and had a chat window (Firefox window) opened. My main Firefox window was also opened as it always is. My main firefox window had approximately 1200 tabs that were synced and have been opening when I open firefox for more than a year. Most of these tabs were very important. Well the main Firefox window was closed with the secondary chat window still opened. Just like that, my massively important 1200 synced tabs were gone!!! Can someone please tell me how to recover them. The tech did open a few blank tabs once i pointed out what had been done. How can I recover all of those tabs? Secondly, can a synced tab session be saved (or backed up) as you used to be able to do in the early days of tabs / session manager? And finally, I need to have my internal drive replaced, is there some way that I can save my open / synced tabs for restoring on new drive after windows reload? Thank you

Chosen solution

Did you look at "History -> Recently Closed Windows" to see if you can reopen this window ?

Note that best is not to click the close X to close a window, but to use the menu to Quit/Exit Firefox.

Use one of these to close Firefox if you are currently doing that by clicking the close X on the Firefox Title bar.

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

You can check if you have a recent upgrade.jsonlz4 file that you can use to restore that lost window.

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 look at this tool to inspect a compressed sessionstore file.

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

Did you look at "History -> Recently Closed Windows" to see if you can reopen this window ?

Note that best is not to click the close X to close a window, but to use the menu to Quit/Exit Firefox.

Use one of these to close Firefox if you are currently doing that by clicking the close X on the Firefox Title bar.

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

You can check if you have a recent upgrade.jsonlz4 file that you can use to restore that lost window.

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 look at this tool to inspect a compressed sessionstore file.

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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Cor-el, you are a lifesaver!!!! First, I have never heard that it was bad to use the X to close out Firefox. I have used that for years. While I will certainly change my habit, I was curious as to why not?

Most importantly, the information that you provided brought my tab back. With a little bit of fuddling around, I got it. Fortunately, my Firefox apparently just did an update yesterday. All of the single tabs that he opened after accidentally closing the multiple tabs had overwritten the backup files. But I found the ONE update file from yesterday that had all of my open tabs as of last night and I was able to get it restored and opened properly. Thank you very much!!! That was a good learning experience too.

So the only way really to back up and potentially restore synced / opened tabs is to back up that sessionstore file, correct?

Thanks again!!