1777136 - Maximized Firefox goes over taskbar set to auto hide on windows

Status: RESOLVED INCOMPLETE

(Core :: Widget: Win32, defect, P3)

Description

[Ara Rezaee]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0

Steps to reproduce:

1. Set your windows taskbar to auto hide
2. Open Firefox and maximize it

Actual results:

Taskbar does not come up (or appear) when you bring the mouse cursor to the bottom of the screen

Expected results:

Taskbar should've came up

I've had this bug for years on different versions of Windows and Firefox, and yet no one has fixed it yet

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Win32' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Ray Kraesig [:rkraesig]]

Do you mean maximized (as you say in the STR) or fullscreen (as you say in the bug title)?

• When Firefox is merely maximized (Alt+Space ⁩→ X), this shouldn't happen, and I can't reproduce it.

• When Firefox is fullscreen (F11), this is the standard behavior in Windows, shared with virtually all other native applications — notably including IE11 and Microsoft Edge, but also full-screen games and presentation apps.

  (The only exceptions I'm aware of are a) UWP apps, which simply force taskbar-autohide behavior regardless of user settings, and b) early versions of IE, which apparently performed some mildly-illicit hackery to show the taskbar anyway.)

Comment 3

[Ara Rezaee]

(In reply to Ray Kraesig [:rkraesig] from comment #2)

Do you mean maximized (as you say in the STR) or fullscreen (as you say in the bug title)?

• When Firefox is merely maximized (Alt+Space ⁩→ X), this shouldn't happen, and I can't reproduce it.

• When Firefox is fullscreen (F11), this is the standard behavior in Windows, shared with virtually all other native applications — notably including IE11 and Microsoft Edge, but also full-screen games and presentation apps.

  (The only exceptions I'm aware of are a) UWP apps, which simply force taskbar-autohide behavior regardless of user settings, and b) early versions of IE, which apparently performed some mildly-illicit hackery to show the taskbar anyway.)

Maximized

Comment 4

[Ara Rezaee]

So I found out that the last good version of firefox for this bug was 67 and the first bad version was 68 (checked all the beta builds of 68 from b3 as well, they all has same issue)

Does this help?

Comment 5

[Ara Rezaee]

Thanks to Reddit I found a solution for this issue, you'll need to set browser.launcherProcess.enabled to false in about:config

I hope those with the same issue as me will find their solution here.

Comment 6

[Gian-Carlo Pascutto [:gcp]]

That's indeed consistent with your bisection of Firefox 67/68: https://bugzilla.mozilla.org/show_bug.cgi?id=1543807

Comment 7

[Ray Kraesig [:rkraesig]]

It's also kind of horrifying! This may require parts of bug 1774703 to further diagnose.

Comment 8

[Ara Rezaee]

Any developments on this? Version 108 also has this issue.

Comment 9

[Ray Kraesig [:rkraesig]]

(In reply to Ara Rezaee from comment #8)

Any developments on this? Version 108 also has this issue.

I'm afraid not. Most launcher-process-related misbehaviors of my acquaintance have been related to either a) highly individual, difficult-to-identify nondefault configurations or b) third-party software (which is often a subset of a)). If they don't appear to affect large numbers of users, they tend to get prioritized lower than things which do appear to. (If you can link the Reddit thread that you mentioned you found that advice on, it might help.)

I can say that this behavior isn't exhibited on a stock Win10 VM. Since you say you've seen this bug for years on different versions of Windows, is there any relatively uncommon software you've used consistently over that timespan that is, or installs, a shell extension? Especially if it claims to interact with or adjust fullscreen apps?

Comment 10

[nyaab00d]

(In reply to Ara Rezaee from comment #5)

set browser.launcherProcess.enabled to false in about:config

God bless you. This is the only thing that's fixed this issue for me.

(In reply to Ray Kraesig [:rkraesig] from comment #9)

I'm afraid not. Most launcher-process-related misbehaviors of my acquaintance have been related to either a) highly individual, difficult-to-identify nondefault configurations or b) third-party software (which is often a subset of a)).

Firefox is the only program that does this. None of the dozens of programs, tools, utilities, etc. I use on this server refuse to show me my taskbar. If it quacks like a duck...
(In reply to Ray Kraesig [:rkraesig] from comment #9)

I can say that this behavior isn't exhibited on a stock Win10 VM. Since you say you've seen this bug for years on different versions of Windows, is there any relatively uncommon software you've used consistently over that timespan that is, or installs, a shell extension? Especially if it claims to interact with or adjust fullscreen apps?

I am using a relatively bare Windows Server 2019 installation and have been tearing my hair out with this issue. Any shell extensions I happen to have installed there are also installed on my other Windows 10 machines - and none of them exhibit this issue. So even if I wanted to try and work backwards by disabling shell extensions, I wouldn't even know where to start - the subset of shell extensions that are on the server are all running on both machines that have never had issues with the taskbar.

As soon as I changed that about:config flag, the issue disappeared. But now I have a far more annoying issue: if Firefox is still open and maximized, and any other window is maximized over it, my taskbar hides and shows itself every few seconds. I have to minimize it entirely to make this stop.

Comment 11

[Ara Rezaee]

(In reply to Ray Kraesig [:rkraesig] from comment #9)

(In reply to Ara Rezaee from comment #8)

Any developments on this? Version 108 also has this issue.

I'm afraid not.

I just installed 114 and the issue seems to be fixed.

(In reply to nyaab00d from comment #10)

(In reply to Ara Rezaee from comment #5)

set browser.launcherProcess.enabled to false in about:config

God bless you. This is the only thing that's fixed this issue for me.

Can you confirm this?

Comment 12

[Ray Kraesig [:rkraesig]]

(In reply to Ara Rezaee from comment #11)

I just installed 114 and the issue seems to be fixed.

That's quite surprising; I don't think there's been any change in any relevant code.

Would you be willing to run mozregression to find what patch introduced the fix? We might be able to write a regression test, or at least reproduce this behavior and and document what led to it.

Comment 13

[BugBot [:suhaib / :marco/ :calixte]]

A needinfo is requested from the reporter, however, the reporter is inactive on Bugzilla. Given that the bug is still UNCONFIRMED, closing the bug as incomplete.

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