1566629 - Pop-up window renders in wrong scale when opened in second monitor

Status: UNCONFIRMED

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

Description

[Leonardo Pereira]

Attachment: Screen Shot 2019-07-16 at 19.03.43.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:68.0) Gecko/20100101 Firefox/68.0

Steps to reproduce:

1. Have a dual monitor setup with different resolutions

• Macbook pro built in display - 2880x1800
• External Ultrawide monitor - 2560 x 1080

2. Open a page on a firefox window in the monitor with the least vertical height (1080p in my case)

3. This page has a link which opens a pop-up window on the main monitor

4. The page renders wrongly, until I move the window from one monitor to another, when it "touches" the area of the another monitor, it renders back to it`s original/normal scale

Actual results:

The page renders wrongly, until I move the window from one monitor to another, when it "touches" the area of the another monitor, it renders back to it`s original/normal scale.

Expected results:

The page renders correctly independently on which monitor the window opens

Comment 1

[Rares Doghi, Desktop QA]

Hi, This issue seems like it might be a duplicate of Bug 1435529 but I'm not entirely sure.

Leonardo can you please try our latest Nightly build and check if the same issue occurs there as well ? You can find the build here: https://nightly.mozilla.org/

Also I will set the component to Widget: Cocoa in case this specific issue does not occur on Windows machines.
I tried to reproduce this issue with 2 normal 1080p monitors and it does not occur.