1279475 - File browser dialogue box on a multi-DPI-scaling setup scales incorrectly

Status: RESOLVED DUPLICATE of bug 1254026

(Core :: Widget: Win32, defect)

Description

[jonno.is]

Attachment: Screenshot of open dialogue, Firefox itself barely visible

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:47.0) Gecko/20100101 Firefox/47.0
Build ID: 20160604131506

Steps to reproduce:

I have a laptop running Windows 10 with a 3840x2160 display set at 200% DPI scaling connected to a 1920x1080 display set at 100% DPI scaling.

I opened a file browser dialogue (e.g. through File > Open..., File > Save Page As, or an actual HTML file element) while Firefox was maximised on the 1920x1080 display.


Actual results:

The browse dialogue is heavily upscaled and completely fills the screen.


Expected results:

The browse dialogue should scale properly as it did in Firefox 46.

Comment 1

[Jonathan Kew [:jfkthame]]

This is a limitation of the current Windows support for per-monitor DPI. A future Windows update will make it possible for us to fix it. See bug 1254026.