1918865 - Unexpected white lines in linear-gradient

Status: NEW

(Core :: Graphics: WebRender, defect)

Description

[Victor Mororó [:vmororo]]

Attachment: test.html

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:130.0) Gecko/20100101 Firefox/130.0

Steps to reproduce:

The test file is attached.
I tested in both Firefox 130.0 and Nightly 132.0a1.
I'm using Ubuntu 22.04.4 LTS.

Actual results:

The gradient is being drawn with two unwanted white lines.

Expected results:

The gradient should be drawn without those white lines.

Comment 1

[Victor Mororó [:vmororo]]

Attachment: firefox-linear-gradient.png

Comment 2

[Victor Mororó [:vmororo]]

Attachment: chromium-linear-gradient.png

Comment 3

[Victor Mororó [:vmororo]]

I tried to reproduce the test case for bug 1888334 on Firefox 130, but the line does not appear on my end.

Comment 4

[Francesco Lodolo [:flod]]

Can't replicate on macOS, assuming it's Linux-only. Please move if there's a more suitable product/component.

Comment 5

[Alice0775 White]

I can reproduce the issue on Nightly132.0a1 Windows11 if HWA is disabled and layout.css.devPixelsPerPx=1.0.

Comment 6

[Alice0775 White]

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=ac2210755eee4932dd2f579a5d81c7afc8455ef8&tochange=bd2a99189b8ae729cf536773d5fb7c64981480c3

Comment 7

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

Set release status flags based on info from the regressing bug 1797721

:lsalzman, since you are the author of the regressor, bug 1797721, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 8

[Victor Mororó [:vmororo]]

Attachment: simpler-examples.html

Additional simplified examples that reproduce the bug

Comment 9

[Victor Mororó [:vmororo]]

(In reply to Victor Mororó [:vmororo] from comment #8)

Created attachment 9424849 [details]
simpler-examples.html

Additional simplified examples that reproduce the bug

I identified specific height values that cause the white line to appear, but only when there is no border.

Comment 10

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

Set release status flags based on info from the regressing bug 1797721