1623022 - One pixel wide gap below address bar

Status: UNCONFIRMED

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

Description

[Fin Christensen]

Attachment: pixel-bar.png

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:74.0) Gecko/20100101 Firefox/74.0

Steps to reproduce:

I had white corners in my Firefox Titlebar like described in https://bugzilla.mozilla.org/show_bug.cgi?id=1558065 and set layers.acceleration.force-enabled to true in about:config.

Actual results:

The white corners disappeared, but a 1 pixel wide gap between the window content and the address bar appeared. This might be a duplicate of https://bugzilla.mozilla.org/show_bug.cgi?id=1422922 I'm not sure as this bug is quite old.

Expected results:

No gap between address bar and window content.

Comment 1

[Simona Badau, Desktop QA]

I can't reproduce it on my Ubuntu 18.04 x64 machine when using Firefox 74 or the latest Nightly 76.0a1.

Christensen, are you using Ubuntu 19.04?

Comment 2

[Fin Christensen]

My System:
Gentoo GNU/Linux
Gnome 3.34.4
Xorg: 1.20.7
Firefox: 74
Graphics Driver: nvidia-drivers-440.64

Comment 3

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

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Comment 4

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

This could either be Graphics, Layout or Widget: GTK...

Comment 5

[Martin Stránský [:stransky] (ni? me)]

It's because we use ARGB visual for the background. I guess default window background was there before you enabled the layers.acceleration.force-enabled.

As a simple test, can you try to set layers.acceleration.force-enabled to false (which turns off GL acceleration) and add mozilla.widget.use-argb-visuals boolean preference, set it to true, restart browser and check if the line is still there?

Thanks.

Comment 6

[Firefox Bug Husbandry Bot]

Because this bug's Severity has not been changed from the default since it was filed, and it's Priority is P3 (Backlog,) indicating it has been triaged, the bug's Severity is being updated to S3 (normal.)

Comment 7

[Fin Christensen]

@stransky I'm sorry I did not answer your question. My laptop mainboard failed and I could not reproduce this issue with another graphics card yet. I am on Intel and AMD graphics now. A friend of mine ran into the same problem on another device, he will provide more information on that.

Comment 8

[johannes]

Attachment: before-floating.png

Hi, I ran into this problem today too (Fedora 33, sway v1.5, Firefox 84.0.1) and Martin's solution worked just fine.
Furthermore, I noticed that this occurs when the first tab is indented (as happens in a floating window).
I attached some screenshots to illustrate how it behaves on my system.

Comment 9

[johannes]

Attachment: before-pinned.png

This is the same window as before but non-floating.