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Bug 771349 - gdk_screen_get_monitor_scale_factor on X11 always returns 1 with GTK 3.21+
gdk_screen_get_monitor_scale_factor on X11 always returns 1 with GTK 3.21+
Product: gtk+
Classification: Platform
Component: Backend: X11
Other Windows
: Normal normal
: ---
Assigned To: gtk-bugs
Depends on:
Reported: 2016-09-13 10:31 UTC by Makoto Kato
Modified: 2016-09-14 10:45 UTC
See Also:
GNOME target: ---
GNOME version: ---

Implement gdk_screen_get_monitor_scale_factor generically (1.27 KB, patch)
2016-09-13 14:45 UTC, Matthias Clasen
committed Details | Review

Description Makoto Kato 2016-09-13 10:31:16 UTC
Firefox cannot respect scale setting with GTK 3.21+.  (

When I am investigating this, I found the regression.

The following changeset removes gdk_screen_get_monitor_scale_factor's X11 implementation.

commit d92fda2103bc79043465b5218323a14edd05183e
Author: Matthias Clasen <>
Date:   Sun Apr 3 00:12:39 2016 -0400

    x11: Port to new monitor api

Please add get_monitor_scale_factor for X11 backend again.
Comment 1 Makoto Kato 2016-09-13 10:46:54 UTC
Or emulate gdk_screen_get_monitor_scale_factor using gdk_display_get_monitor and gdk_monitor_get_scale_factor...
Comment 2 Matthias Clasen 2016-09-13 14:45:53 UTC
Created attachment 335442 [details] [review]
Implement gdk_screen_get_monitor_scale_factor generically

This was forgotten when the other screen monitor apis were
ported to GdkMonitor.
Comment 3 Matthias Clasen 2016-09-14 10:45:42 UTC
Attachment 335442 [details] pushed as 21bdf61 - Implement gdk_screen_get_monitor_scale_factor generically