1663194 - Custom Title Bar corners are not transparent on Ubuntu 20.04

Status: RESOLVED FIXED

(Core :: Widget: Gtk, defect, P2)

Description

[Alice0775 White]

Attachment: screenshot

+++ This bug was initially created as a clone of Bug #1460959 +++

Unfortunately, Bug 1460959 does not fix the browser corner rendering issue.
Nonetheless, the native title bar are disabled by default :(

Steps to reproduce:

1. Start Nightly with new profile
2. Unmaxmized window if necessary

Actual results:
Title bar has white background in top left and right corners.

Expected results:
Top corners should have transparent background.

Comment 1

[Alice0775 White]

Attachment: about:support

Comment 2

[user142]

I can confirm this bug when starting Firefox with LIBGL_ALWAYS_SOFTWARE=1 ./firefox

Comment 3

[user142]

I can also confirm this bug when force-disabling WebRender (setting gfx.webrender.force-disabled to true) so for me this bug happens with the Basic and OpenGL compositors but does not happen with WebRender.
When I enable EGL on X11 (MOZ_X11_EGL=1) I can see black corners instead of white corners even with WebRender enabled.

Comment 4

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

I see, I'll need to test Ubuntu then, Thanks.

Comment 5

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

Can you please attach your desktop related ENV variables?

Run on terminal:

env | grep XDG

and attach the output here.
Thanks.

Comment 6

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

Hm, I'm unable to reproduce it. Can you try to create a new profile, disable WebRedner at about:config, restart browser and check the corners?
Thanks.

Comment 7

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

Please re-test as Bug 1663279 landed.
Thanks.

Comment 8

[Alice0775 White]

yes, no longer reproduce the issue on Nightly82.0a1(20200907153413).