1653919 - Glitches on the bottom of the browser when activating Title Bar

Status: NEW

(Core :: Graphics, defect, P3)

Description

[Alexandru Trif, QA [:atrif]]

Attachment: tittle_bar_00.gif

Affected versions

• 80.0a1 (20200719185002)
• 79.0b9 (20200717001501)
• 78.0.2 (20200708170202)

Affected platforms

• Windows 10x64

Steps to reproduce

1. Open Firefox Customize menu.
2. Activate/Deactivate Title Bar and observe the bottom of the browser.

Expected result

• No glitches presented.

Actual result

• Bottom of the browser is mirrored shortly when activating Title Bar.

Regression range

• Last good revision: afa70e5e516abf11f4760b915c0b3d09bc351147 (2019-01-31)
• First bad revision: 024bef408a8896f365789759f6a3b6e00daf5aca (2019-02-01)
• Pushlog:
  https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=afa70e5e516abf11f4760b915c0b3d09bc351147&tochange=024bef408a8896f365789759f6a3b6e00daf5aca

Notes

• Attached a screen recording.
  Severity S3

Comment 1

[Mike Conley (:mconley) (:⚙️) (PTO: May 24 - June 2nd)]

Hi atrif,

On a machine where you can reproduce this, can you please post the about:support text?

Comment 2

[Alexandru Trif, QA [:atrif]]

Attachment: aboutsupport.txt

(In reply to Mike Conley (:mconley) (:⚙️) from comment #1)

Hi atrif,

On a machine where you can reproduce this, can you please post the about:support text?

Hi! Attaching contents of about:support. The issue is reproducing with WebRender off and on.
If more information is needed please let me know. Thanks!

Comment 3

[Mike Conley (:mconley) (:⚙️) (PTO: May 24 - June 2nd)]

Hey jimb, just taking a shot in the dark here - does the GIF in comment 0 suggest to you that this is a problem in our graphics layer? Or is it more likely a problem in our widget layer? Or something else entirely?

Comment 4

[Jim Blandy :jimb]

I guess a reasonable first step of debugging this would be to look at the frame tree behavior while that toggle is getting switched. If the frame tree gets updated precisely as the window gets reconfigured, then it'd be a downstream (i.e. graphics) problem. If there's a lag between the window reconfiguration and the frame tree update, then it'd be an upstream (i.e. widget) problem.

I think it would be reasonable for the graphics team to look into that, and kick it back to widget if it's an upstream issue.

Comment 5

[Release mgmt bot [:sylvestre / :calixte / :marco for bugbug]]

The severity field is not set for this bug.
:Gijs, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 6

[:Gijs (he/him)]

(In reply to Jim Blandy :jimb from comment #4)

I guess a reasonable first step of debugging this would be to look at the frame tree behavior while that toggle is getting switched. If the frame tree gets updated precisely as the window gets reconfigured, then it'd be a downstream (i.e. graphics) problem. If there's a lag between the window reconfiguration and the frame tree update, then it'd be an upstream (i.e. widget) problem.

I think it would be reasonable for the graphics team to look into that, and kick it back to widget if it's an upstream issue.

Punting this to gfx-land based on this comment.