Can't you close Window?

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

You can check "History -> Restore Previous Session" and "History -> Recently Closed Windows/Tabs".

• https://support.mozilla.org/en-US/kb/restore-previous-session

Hi cor-el, thanks for your reply. Closing it down doesn't work.

For instance, just now I had five tabs open on Window 1 (Current), and all the other tabs that I want back were on Window 2, as shown in the image. I closed down Window 1 using X in the title bar. I then reopened Firefox and the five tabs were gone. This also happens when I use the 3 bar menu to Exit the program.

Whatever I do, every time it opens, it opens with no tabs in a new window which is Window 1, and won't let me switch to Window 2.

Hi Mike, you probably already know about these menu items to reopen a closed windows, but just in case:

• menu button > History > Recently Closed Windows
• (optional top menu bar / tap Alt) History > Recently Closed Windows

Normally you can switch between windows using the Windows Taskbar. However, if one of the windows has mistakenly moved completely off the screen, you won't be able to see it. Could that be the issue with Window #2?

In that case, it might help to maximize it. After activating Window #2, press Alt+Spacebar then press x to maximize. Does that allow you to close both of those tabs so you are back to one main window?

Hello jscher, I tried >Recently closed windows but none of the windows that it opened were Window 1 with all the tabs in it. They were all versions of Window 2 that I've been using.

When I try Alt + Spacebar the 'restore move size' context menu appears in the top left, but pressing x does nothing, and on the context menu the option for maximise is greyed out.

I went into Taskbar settings and disabled the 'combine when taskbar is full' option, but no new Firefox windows appeared.

Hmm, is the missing window still listed on Firefox View (the panel shown in your original screenshot)?

Assuming so:

What should happen is that you could click one of the tabs listed in any window, and that tab should be brought into view. When you tried that, what happened?

If what happened is that you didn't see the new window but the other window became inactive -- usually there's a change in the title bar that signals this, such a text fading or a different color -- try the Alt+Spacebar > Maximize trick at that point.

If that still doesn't work, then:

You can remove the file that stores window dimensions/positions in case it has become corrupted with nonsensical values. Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > Help > More Troubleshooting Information
• (menu bar) Help > More Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows File Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

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

Pause while Firefox finishes its cleanup, then:

Right-click xulstore.json then click Rename and add OLD so it becomes xulstoreOLD.json

Start Firefox back up. Do windows display normally again?

Thank you, jscher! Clicking in the list of tabs under the inactive Window was all that it took! So simple! If any developers are watching, a short sentence of contextual help text on that page explaining this would have saved me 48 hours of frustration.

jscher, should I continue and follow the second half of your advice as a maintenance precaution, or does the result, above, indicate this is not necessary?

You could save the extra steps for later in case clicking a tab on the list stops working.

I've just discovered a new problem. Not as bad, but annoying and breaks workflow.

I am working with my tabs in Window 1. I click away to another app and when I return to Firefox, Window 1 is no longer open. Instead, Window 2 is open again. I have to do as advised above: go onto the Open Tabs page of Firefox View (as shown in the screenshot) and click into Window 1 to return to it.

When I go onto Open Tabs, I also noticed that Window 2 is still listed as the current tab. Window 1 is never shown as current.

How do I delete Window 2 and/or assign Window 1 as the current tab?

Are there any tabs you need in Windows 2? If not, you should be able to individually close those tabs and after you close the last tab, Window 2 should close automatically. Or use the X button on Windows 2 (on the title bar of the window, I don't think you can do it through Firefox View).

Tried closing those tabs as you suggest but when I shut down the browser and start it up, again, it opens a new second window as current, and my working tabs are all in the other window.