Backed out changeset 0f052f1a6a05 (bug 1272332)

modules/libpref/init/all.js

@@ -4569,7 +4569,6 @@ pref("gfx.apitrace.enabled",false);
 pref("gfx.content.use-native-pushlayer", true);
 #ifdef MOZ_WIDGET_GTK
 pref("gfx.xrender.enabled",false);
-pref("widget.allow-gtk-dark-theme", false);
 #endif
 #endif
 

widget/gtk/nsLookAndFeel.cpp

@@ -1098,21 +1098,16 @@ nsLookAndFeel::Init()
     // with wrong color theme, see Bug 972382
     GtkSettings *settings = gtk_settings_get_for_screen(gdk_screen_get_default());
 
+    // Disable dark theme because it interacts poorly with widget styling in
+    // web content (see bug 1216658).
+    // To avoid triggering reload of theme settings unnecessarily, only set the
+    // setting when necessary.
+    const gchar* dark_setting = "gtk-application-prefer-dark-theme";
+    gboolean dark;
+    g_object_get(settings, dark_setting, &dark, nullptr);
 
-    bool allowDarkTheme = mozilla::Preferences::GetBool("widget.allow-gtk-dark-theme", false);
-
-    if (!allowDarkTheme) {
-        // Disable dark theme because it interacts poorly with widget styling in
-        // web content (see bug 1216658).
-        // To avoid triggering reload of theme settings unnecessarily, only set the
-        // setting when necessary.
-        const gchar* dark_setting = "gtk-application-prefer-dark-theme";
-        gboolean dark;
-        g_object_get(settings, dark_setting, &dark, nullptr);
-
-        if (dark) {
-            g_object_set(settings, dark_setting, FALSE, nullptr);
-        }
+    if (dark) {
+        g_object_set(settings, dark_setting, FALSE, nullptr);
     }
 
     GtkWidgetPath *path = gtk_widget_path_new();