1822465 - About Firefox dialog has invalid size on lower dpi display

Status: UNCONFIRMED

(Core :: Widget: Win32, defect, P3)

Description

[Virgo Pärna]

Attachment: about_before_dragging.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/111.0

Steps to reproduce:

I have two displays connected to my computer (laptop) running Windows 10.
internal display is 200dpi (250% scaling)
external display is 96 dpi (100% scaling).
System dpi is 200 (250% scaling)
Firefox Window is on lower-dpi screen (it opened on that).
I open About Firefox dialog

Actual results:

There is black frame at right and bottom edge of window around blue background. (Actually same thing happened to master master password entry dialog, but I did not test it with that). And right edge is also visibly wider then left edge. But when I drag that window to main display and back, that black area is filled with main background colour and content is centered without fixing Window size.

Expected results:

About window should open without black frame and also without additional padding.

Comment 1

[Virgo Pärna]

Attachment: about_after_dragging.png

That is how window looks after dragging it to main (high dpi) display and back again

Comment 2

[Virgo Pärna]

Attachment: password_before_dragging.png

Also example with master/primary password prompt. Here it is clearer, because of gray background.

Comment 3

[Virgo Pärna]

Attachment: password_after_dragging.png

And same master/primary password prompt after dragging it to main display and back.

It is a very minor issue, but I though that I report it anyway. It probably has been in Firefox for some time in some form or another. It was once "fixed", but I think, that fix ended up just filling entire Window content area (like it happens now after dragging Window) - because password prompts seemed still too high. Also, then it was visible only in height.
Bug 1718786
Maybe total Windows height is calculated with Window borders size calculated with default dpi instead of current display dpi?