1536409 - CSS is rendered incorrectly when display or browser is scaled

Status: NEW

(Core :: Graphics, defect, P3)

Description

[Alexandra Govorkova]

Attachment: spinner(125).PNG

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36

Steps to reproduce:

1. Make sure that you display in OS settings and browser has 100% scaling
2. Open https://jsfiddle.net/t1ajc75y/1/
3. Observe correct spinner in the right bottom part of page.

Variant 1:
4. Open Firefox menu and set zoom 120%

Variant 2:
4. Go to OS display settings (on Windows 10 it is settings->system->display)
5. Set scaling 125% to the current display.

Actual results:

Spinner is displayed with artifacts (see screenshot)

Expected results:

Spinner should look the same as with 100% scaling.

This issue seems not to be reproduced with previous versions.
The issue is reproduced with Nightly v68.

Comment 1

[Alexandra Govorkova]

Updates:
The issue is reproduced on Firefox 61 (Windows 10).
The issue is not reproduced on Mac.

Comment 2

[Emilio Cobos Álvarez [:emilio]]

Given this doesn't happen on mac it's likely either a graphics or a widget issue.

Comment 3

[Jessie [:jbonisteel] pls NI]

Can you find a regression window using https://mozilla.github.io/mozregression/ ?

Comment 4

[Alexandra Govorkova]

Jessle, sorry, I was wrong about older versions of Firefox. I just downloaded and checked 30.0 and 40.0.3, the bug is reproduced. I think there is no sense to check other versions.