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Restore previous tabs issue when a tab(s) is split between screens

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I had 20 tabs open on one screen. I moved one tab off the the 2nd screen so I could see info between two pages at the same time. When I was done, I closed the browser with the 19 tabs so I was left with one tab browser on the 2nd screen. Unfortunately now I lost all 19 tabs because when I click restore Recently Closed Windows (tabs) the only thing that listed is the tab I already have open.

This has been an issue for a LONG time. I have to remember to close the temporary browser tab 1st then close the main browser with all the other tabs open LAST. I HATE that I lose everything if I don't close the split browser in that order.

I had 20 tabs open on one screen. I moved one tab off the the 2nd screen so I could see info between two pages at the same time. When I was done, I closed the browser with the 19 tabs so I was left with one tab browser on the 2nd screen. Unfortunately now I lost all 19 tabs because when I click restore Recently Closed Windows (tabs) the only thing that listed is the tab I already have open. This has been an issue for a LONG time. I have to remember to close the temporary browser tab 1st then close the main browser with all the other tabs open LAST. I HATE that I lose everything if I don't close the split browser in that order.

All Replies (4)

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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 or Private Browsing 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
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When you tear a tab off to a separate window and close the first window before the separate window, you should be able to get the first window back from the History menu. Either:

  • "3-bar" menu button > History > Recently Closed Windows
  • optional "Library" toolbar button > History > Recently Closed Windows
  • (menu bar) History > Recently Closed Windows

By default, Firefox only remembers 3 closed windows, so do this ASAP. If you want Firefox to remember more closed windows, there is a preference for that:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future. Since we have had this setting for a long time and I use it myself, I feel comfortable mentioning it.

(2) In the search box in the page, type or paste browser.sessionstore.max_windows_undo and pause while the list is filtered

(3) Double-click the preference to display an editing field, and change the value to 5 or whatever sounds safe to you, then press Enter or click the blue check mark button to save the change.

(Note that very high values will slow your Firefox a bit because Firefox saves the session history as often as 4 times per minute.)

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Thank you for your reply. I'm familiar with the History Recently Closed location as I've had to use it a few times after tearing off one tab off the main window then closing the main window and all the tabs I had open are gone, replaced by the one tab torn off the main window.

What happened this time is my Recently Closed tabs in History wasn't there. All that was there were one-off tabs not all 10 or so tabs I had open. I did try this right after realizing the tear off tab was still lingering in the background.

I increased the value a little higher than 3 based off your instructions. Hopefully it'll help. There should be a way for FireFox to prompt that I'm about to close a browser with a lot of tabs open, are you sure you want to proceed or just have it remember by default until tabs are manually closed.

Modified by Starman

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Just to make sure we are discussing the same menu, you'll need to check Recently Closed Windows instead of Recent Closed Tabs (the tabs list is per window and not global). Or try Ctrl+Shift+N to restore the last-closed window.

Also, the safest way to close Firefox if you don't want to lose any closed windows -- all the windows will be considered open windows at the next restore -- is the menu command. Either:

  • "3-bar" menu button > Exit
  • (menu bar) File > Exit