1517282 - Starts up in full screen on dual-screen setup when title bar is disabled

Status: UNCONFIRMED

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

Description

[Arnaud Meyer]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:64.0) Gecko/20100101 Firefox/64.0

Steps to reproduce:

Debian testing with Firefox 64.0-amd64 and MATE desktop 1.20.3

1. Start Firefox with a new/empty profile
2. Menu > Customize > Uncheck "Title bar" at the bottom
3. Close Firefox
4. In a dual-screen setup, open Firefox on a secondary screen


Actual results:

Firefox starts in full screen (F11) mode, regardless of previous settings. It reproduces upon every launch as long as title bar is disabled.

Strangely enough, this only happens on a secondary screen of a dual-screen setup. Starting Firefox the same way on the primary screen does not automatically enable full screen mode.


Expected results:

Firefox should behave as it does on a single screen setup or when title bar is enabled : remember last applied fullscreen settings, or leave the choice to the user (preferences/about:config).

Comment 1

[Peter Magyari (Desktop QA)]

Hi,

I wasn't able to reproduce this issue on Debian / Ubuntu 18.04 using Firefox 64.0 or Firefox Nightly 66.0a1.

Please test if it occurs to you on the latest Firefox Nightly, you can download it from here:
https://www.mozilla.org/en-US/firefox/channel/desktop/

Also, please test if the issue is reproducible in safe-mode. Here is a link that can help you with that:
https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

Thank you for reporting!

Comment 2

[Arnaud Meyer]

Hi,

I was able to reproduce the problem using Nightly firefox-66.0a1.en-US.linux-x86_64 (I used a new, empty profile).

However, I could not reproduce it in Safe mode, but that let me understand that I forgot a step in my description:

1. Start Firefox with a new/empty profile
2. Menu > Customize > Uncheck "Title bar" at the bottom
3. Maximize window (I forgot this step)
4. Close Firefox
5. In a dual-screen setup, open Firefox on a secondary screen

As Safe mode does not appear to remember maximized window state, the bug is not reproducible in this case.

Note also that when Firefox starts in this undesired fullscreen mode, the address and menu bar are not disappearing instantly; they do so after clicking in the main browser window, which makes this bug a little but more annoying.

Thank you for your support.

Comment 3

[Peter Magyari (Desktop QA)]

I'm going to set a component in order to involve the development team in reviewing this issue.

Comment 4

[Mike de Boer [:mikedeboer]]

This looks like an issue that's very specific to the window manager used. Since the session restore code is very generic in this case - and doesn't have the notion of multiple displays or even desktops to restore to, it's very unlikely that the bug is in there.