File libqt5-prioritise-gtk2-platformtheme.patch of Package libqt5-qtbase

Index: qtbase-opensource-src-5.9.1/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp
===================================================================
--- qtbase-opensource-src-5.9.1.orig/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp
+++ qtbase-opensource-src-5.9.1/src/platformsupport/themes/genericunix/qgenericunixthemes.cpp
@@ -828,7 +828,9 @@ QStringList QGenericUnixTheme::themeName
                 result.push_back(QLatin1String(QKdeTheme::name));
 #endif
             } else if (gtkBasedEnvironments.contains(desktopName)) {
-                // prefer the GTK3 theme implementation with native dialogs etc.
+                // prefer the GTK+2 theme implementation with the native style, etc.
+                result.push_back(QStringLiteral("gtk2"));
+                // prefer second the GTK+3 theme implementation with native dialogs, etc.
                 result.push_back(QStringLiteral("gtk3"));
                 // fallback to the generic Gnome theme if loading the GTK3 theme fails
                 result.push_back(QLatin1String(QGnomeTheme::name));