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Bug - Incorrect "You are about to close 2 windows with 2 tabs..." Message

  • 12 replies
  • 3 have this problem
  • 10 views
  • Last reply by robtoe

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Just updated to 63.0 earlier today.

I typically run a separate instance of FF (streaming audio) in the background, and may launch a separate instance of FF for browsing on and off.

Upon closing the separate (browsing) instance, I get the tab closing message of "you are about to close 2 windows with 2 tabs...". This is incorrect, as closing the browsing instance does not affect the streaming audio instance I have running.

To confirm, I closed the streaming audio instance, and then closed the browsing instance, the message does not appear. In other words, FF now incorrectly thinks the 2 instances are connected, and closing one will affect the other - it does not.

Did not occur until after the update today.

Just updated to 63.0 earlier today. I typically run a separate instance of FF (streaming audio) in the background, and may launch a separate instance of FF for browsing on and off. Upon closing the separate (browsing) instance, I get the tab closing message of "you are about to close 2 windows with 2 tabs...". This is incorrect, as closing the browsing instance does not affect the streaming audio instance I have running. To confirm, I closed the streaming audio instance, and then closed the browsing instance, the message does not appear. In other words, FF now incorrectly thinks the 2 instances are connected, and closing one will affect the other - it does not. Did not occur until after the update today.

Modified by robtoe

All Replies (12)

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Hi robtoe, how were you closing the non-audio window? For example:

  • click the X button at the upper right of the window
  • using Exit from the menu
  • some other method

What method do you use to start a separate instance of Firefox?

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Hi - I use the "X" for the non-audio window, and launch all instances of FF via Start -> Most Used (Win 10).

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Usually if you use the same shortcut to launch multiple Firefox windows, they are all part of the same instance/session. You actually need to use a couple command line parameters to start independent instances/sessions of Firefox.

But I thought the "X" button just closed the current window of Firefox, not all windows of Firefox. That hasn't changed for me in Firefox 63 on Windos 7. Maybe it's a Windows 10 thing?

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Assumed they were separate instances.

In any event, closing the browsing session/window does not close the audio session/window, so there shouldn't be a warning message about it.

Also, as mentioned, this started occurring today, immediately after the update. Did not occur over the several years I've been using FF.

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Hmm, I can't replicate it. Mine just says "two tabs" like normal when I click the "X". Hopefully another Windows 10 user can see whether it has changed on theirs.

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Thanks for the help, but we may have gotten sidetracked: there should be no message offered in this scenario.

If 2 FF windows are open, closing one of them does not affect the other. There is no need to throw a warning message about something that will not occur.

I would have suggested that FF had become unable to differentiate between windows and tabs under 63.0, however - at least on Win10 - the messaging actually mentions both.

In your testing, I'm a bit suspicious of a bug as well. You're saying you have 2 FF windows open, and closing 1 window also closes the other? If so, FF cannot differentiate between a tabbed session and windowed (which I'd be surprised by). Otherwise, if closing one window does not affect the other, you seeing the same superfluous message, mentioned in my bug.

[And yes, I could uncheck the tab closing warning, but it has saved me a few times. I just don't want to see it when it does not apply.]

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No, mine has the default behavior:

  • I have two windows open, with two tabs each
  • Click X in one window, get the "two tabs" warning, no reference to two windows
  • Proceeding closes only that window

No changes from normal Firefox behavior of recent years.

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I'm referring to closing a window with only 1 tab, yet getting the multi-tab warning.

Here's the repro:

1. Using a single tab only, head to sportsnet.ca/590/, choosing to "Listen Live". 2. FF "mini player launches" in separate window. 3. Close original FF window.

Result: Get "tab closure warning". Expect: No message. (As with pre 63.0.) Detail: Closing the main FF window does not impact the player window. No warning required.

4. Launch another FF window, with player window still streaming. 5. Use only a single tab for browsing, close this window.

R - E - D is same as after step 3. No closure warning required.

This is a minor annoyance, and I've since turned off the multi-tab warning, but should not have to. This is new behaviour with 63.0.

Gist: don't warn for no reason.

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Hi robtoe, okay, I see the pattern here:

Here's the repro:

1. Using a single tab only, head to sportsnet.ca/590/, choosing to "Listen Live".
2. FF "mini player launches" in separate window.
3. Close original FF window.

Result: Get "tab closure warning".
Expect: No message. (As with pre 63.0.)

Start with a single window and load the above page, or this test page: https://www.jeffersonscher.com/res/popit.html

Click the player link to launch a pop-up window with restricted features --

window.open(web_player_url, 'ListenLiveWindow', 'width=' + _this.web_player_width + ',height=' + _this.web_player_height + ',status=0,scrollbars=0,resizable=0');

-- or the third link on the test page.

Click the X button on the main window and get the attached bizarre message.

This message would only make sense if the pop-up was a dialog window that automatically closes with the main window. Since it stays open, the message does not make sense.

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Exactly. Prior to 63.0 the warning did not appear in that scenario.

No biggie, as I've disabled the multi-tab warning, but one day it will burn me when I accidentally close a multi-tab window in error.  :)

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It seems easier to put up with the erroneous message than to go without protection, but that's up to you.

I filed a bug report: https://bugzilla.mozilla.org/show_bug.cgi?id=1502179

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My use case involves launching and closing that separate FF window dozens of times a day.