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[NOT Solved]Closed main window while Private still worked and lost all tabs/session.

  • 2 replies
  • 1 has this problem
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  • Last reply by rey0n

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It's really dumb that one can close own Main window without warning that too many tabs are closed or there is another window still running! And that's what happened to me: i had Private window in back, closed Main window thinking that i'm closing browser, and then surprisingly saw Private window is still there. As any ordinary user who already lost tabs in past i panicked and closed the Private window too. Started Firefox once again hoping for restore, but it opened with clear window and obviously there was no "Restore session" button in Menu, as i have "Auto restore" ON in settings.

I started to search for manual way, found descriptions with manual renaming/coping backups from sessionstore-backup folder. Like these= https://support.mozilla.org/de/questions/1275314 https://support.mozilla.org/en-US/questions/1310742 But however i tried to copy and rename - each start Firefox ignores that, clears backup folder and again clear window. Lucky i thought about coping those recover. and previous. files from sessionstore-backup folder after first browser close, so they are safe. And i'm sure my tabs are still there = checked it with https://www.jeffersonscher.com/res/scrounger.html.

So yeah, i have at least some way to get back tabs, but i'm really angry and curious to know WHAT is forbidding me to restore that file after manual rename??!

It's really dumb that one can close own Main window without warning that too many tabs are closed or there is another window still running! And that's what happened to me: i had Private window in back, closed Main window thinking that i'm closing browser, and then surprisingly saw Private window is still there. As any ordinary user who already lost tabs in past i panicked and closed the Private window too. Started Firefox once again hoping for restore, but it opened with clear window and obviously there was no "Restore session" button in Menu, as i have "Auto restore" ON in settings. I started to search for manual way, found descriptions with manual renaming/coping backups from sessionstore-backup folder. Like these= https://support.mozilla.org/de/questions/1275314 https://support.mozilla.org/en-US/questions/1310742 But however i tried to copy and rename - each start Firefox ignores that, clears backup folder and again clear window. Lucky i thought about coping those recover. and previous. files from sessionstore-backup folder after first browser close, so they are safe. And i'm sure my tabs are still there = checked it with https://www.jeffersonscher.com/res/scrounger.html. So yeah, i have at least some way to get back tabs, but i'm really angry and curious to know WHAT is forbidding me to restore that file after manual rename??!

Modified by rey0n

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Did you look for closed windows in "History -> Recently Closed Tabs/Windows" ?

If Firefox recently updated then look for a upgrade.jsonlz4 file.

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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@cor-el Hello. As i stated above i tried all the variant of renaming, including simple renaming and "scroungering" via https://www.jeffersonscher.com/res/scrounger.html to get not zipped sessionstore.json = it doesn't work, FF simply "ignores" exchanged files and deletes those creating new/clear ones. "History -> Recently Closed Tabs/Windows" wasn't available since beginning, as i think due to Private tab was closed last(after Main window, which got "erased" due to no safety check for such situation). Plus during trying "renaming magic" i started and closed FF several times. I have sessionstore-backup safe and files there are alive with proper tabs, just FF keeps erasing them if try to insert any(recovery or previous).

That's why i'm asking What may be forbidding FF to take renamed files?(files aren't corrupted for sure)