diff --git a/ui/ui_utility.cpp b/ui/ui_utility.cpp
index e66055d..1086704 100644
--- a/ui/ui_utility.cpp
+++ b/ui/ui_utility.cpp
@@ -14,7 +14,6 @@
 #include <QtGui/QtEvents>
 #include <QWheelEvent>
 
-#include <private/qguiapplication_p.h>
 #include <private/qhighdpiscaling_p.h>
 
 #include <array>
@@ -214,11 +213,6 @@ bool IsContentVisible(
 		&& !widget->window()->isMinimized();
 }
 
-void DisableCustomScaling() {
-	QHighDpiScaling::setGlobalFactor(1);
-	QGuiApplicationPrivate::resetCachedDevicePixelRatio();
-}
-
 int WheelDirection(not_null<QWheelEvent*> e) {
 	// Only a mouse wheel is accepted.
 	constexpr auto step = static_cast<int>(QWheelEvent::DefaultDeltasPerStep);
diff --git a/ui/ui_utility.h b/ui/ui_utility.h
index 80764f9..420f0ff 100644
--- a/ui/ui_utility.h
+++ b/ui/ui_utility.h
@@ -194,8 +194,6 @@ QPointer<const Widget> MakeWeak(not_null<const Widget*> object) {
     not_null<QWidget*> widget,
     const QRect &rect = QRect());
 
-void DisableCustomScaling();
-
 int WheelDirection(not_null<QWheelEvent*> e);
 
 } // namespace Ui