1679335 - Scaling of Firefox doesn't adjust when moved across Monitors with Different DPis

Status: RESOLVED WONTFIX

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

Description

[patrickgarraud44]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:83.0) Gecko/20100101 Firefox/83.0

Steps to reproduce:

Moved Firefox from a window with 100% scaling to one with 200% scaling or vice versa.

Actual results:

The window and Web contents retained the scaling from the original window

Expected results:

The window to automatically adjust to the scaling of the window it's in.

(Ubuntu Bug Report: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1905337)

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Comment 2

[Jim Mathies [:jimm]]

We have some reports that this is happening on Windows. We did some pretty exhaustive testing of scaling with multi-monitor system in the spring and didn't find anything, so maybe there's a recent regression.

Comment 3

[Jim Mathies [:jimm]]

Resetting things, and will file a fresh bug on the Windows issue.

Comment 4

[Martin Stránský [:stransky] (ni? me)]

X11 does not support it AFAIK. Please try Wayland desktop in Ubuntu 20.04 although the support is still not 100% perfect - there are some glitches when window is moved across monitors and popups are sometimes invisible - but that will be fixed.

Comment 5

[patrickgarraud44]

(In reply to Martin Stránský [:stransky] (ni? me) from comment #4)

X11 does not support it AFAIK. Please try Wayland desktop in Ubuntu 20.04 although the support is still not 100% perfect - there are some glitches when window is moved across monitors and popups are sometimes invisible - but that will be fixed.

This was tested in Wayland.

Comment 6

[Martin Stránský [:stransky] (ni? me)]

Good.
Can you please create a screencast of the issue?
https://help.gnome.org/users/gnome-help/stable/screen-shot-record.html
(the screencast records all monitor so it will be visible there)
Thanks.

Comment 7

[patrickgarraud44]

Attachment: Firefox Scaling Issue

Comment 8

[Martin Stránský [:stransky] (ni? me)]

So you have primary screen with 200% scale, secondary with 100% scale, right?
Please

1. attach content of about:support page.
2. run Firefox with MOZ_LOG="Widget:5" env variable and attach the log here.

Looks Firefox does not get 'scale change' event.
Thanks.

Comment 9

[patrickgarraud44]

Attachment: About Support Page

Comment 10

[Martin Stránský [:stransky] (ni? me)]

Yes, scaling is not supported on X11. You need to use Wayland backend for it.