1603310 - Layout is broken when displayed on a wide screen

Status: RESOLVED INCOMPLETE

(Core :: Layout, defect, P3)

Description

[Karl Dubost💡 :karlcow]

The two vertical panels should be side-by-side (as they are in Chrome) but they overlap. If I make the window more narrow, however, the layout is fixed.

This is difficult to investigate.

• It doesn't reproduce on Linux Ubuntu
• It doesn't reproduce on macOS
• It reproduces for some Windows 10 computers (3 different so far Japanese and English OS)
• It doesn't reproduce on @softvision-sergiulogigan Windows 10 Pro computer.
• WebRender on/off doesn't change anything.

Brian added:

So far I have reproduced on:

• Firefox versions: Nightly 73, Beta 72, and Nightly 70 (prior to updating).
• Firefox profiles: Three different profiles two of which are clean.
• Hardware: three different computers, two of which have different graphics cards and all of which have different monitors (I suspect they all have display density of 2 device pixels per logical CSS pixel however).
• OS versions: Windows 10 Pro 1903 ja and Windows 10 Pro 1803 en.

Comment 1

[Cameron McCormack (:heycam)]

Is this a regression, or on the machines / OSes where this is reproducible you get the same behavior with old Firefoxes?

Comment 2

[Brian Birtles (:birtles, Feb 26~ parental leave)]

I don't think it's a regression. It reproduces in Beta 72 and I tested on a computer with a old copy of Nightly 70 and it reproduced there too.

Comment 3

[Emilio Cobos Álvarez (:emilio)]

I can't repro at all... Testing older builds than the mentioned in comment 2 may be useful, just in case... Maybe dependent on font metrics?

Comment 4

[Brian Birtles (:birtles, Feb 26~ parental leave)]

I'm specifically seeing this in Windows 10 Pro 1903 ja and Windows 10 Pro 1803 en.

Perhaps Karl can reduce it when he next visits the office.

Comment 5

[Ksenia Berezina [:ksenia]]

The link is redirecting to the main page now.