File mate-control-center-gtk-3.20.patch of Package mate-control-center

--- a/capplets/appearance/appearance-desktop.c
+++ b/capplets/appearance/appearance-desktop.c
@@ -883,11 +883,20 @@ static gdouble
 get_monitor_aspect_ratio_for_widget (GtkWidget *widget)
 {
   gdouble aspect;
+#if GTK_CHECK_VERSION (3, 22, 0)
   GdkMonitor *monitor;
+#else
+  int monitor;
+#endif
   GdkRectangle rect;
 
+#if GTK_CHECK_VERSION (3, 22, 0)
   monitor = gdk_display_get_monitor_at_window (gtk_widget_get_display (widget), gtk_widget_get_window (widget));
   gdk_monitor_get_geometry (monitor, &rect);
+#else
+  monitor = gdk_screen_get_monitor_at_window (gtk_widget_get_screen (widget), gtk_widget_get_window (widget));
+  gdk_screen_get_monitor_geometry (gtk_widget_get_screen (widget), monitor, &rect);
+#endif
 
   aspect = rect.height / (gdouble)rect.width;
 
--- a/capplets/common/capplet-util.c
+++ b/capplets/common/capplet-util.c
@@ -76,7 +76,11 @@ capplet_help (GtkWindow *parent, char co
 
 	uri = g_strdup_printf ("help:mate-user-guide/%s", section);
 
+#if GTK_CHECK_VERSION (3, 22, 0)
 	if (!gtk_show_uri_on_window (parent , uri, gtk_get_current_event_time (), &error)) {
+#else
+	if (!gtk_show_uri (gtk_window_get_screen (parent), uri, gtk_get_current_event_time (), &error)) {
+#endif
 		capplet_error_dialog (
 			parent,
 			_("There was an error displaying help: %s"),
--- a/configure.ac
+++ b/configure.ac
@@ -59,8 +59,8 @@ AC_CHECK_FUNC(XScreenSaverQueryInfo, [
 AC_SUBST(TYPING_BREAK)
 AC_SUBST(SCREENSAVER_LIBS)
 
-GLIB_REQUIRED=2.50.0
-GTK_REQUIRED=3.22.0
+GLIB_REQUIRED=2.48.0
+GTK_REQUIRED=3.20.0
 MARCO_REQUIRED=1.17.0
 MSD_REQUIRED=1.17.0
 MATEKBD_REQUIRED=1.17.0
--- a/libslab/slab-mate-util.c
+++ b/libslab/slab-mate-util.c
@@ -118,7 +118,11 @@ open_desktop_item_help (MateDesktopItem
 		help_uri = g_strdup_printf ("help:%s", doc_path);
 
 		error = NULL;
+#if GTK_CHECK_VERSION (3, 22, 0)
 		if (!gtk_show_uri_on_window (NULL, help_uri, gtk_get_current_event_time (), &error))
+#else
+		if (!gtk_show_uri (libslab_get_current_screen (), help_uri, gtk_get_current_event_time (), &error))
+#endif
 		{
 			g_warning ("error opening %s [%s]\n", help_uri, error->message);
 
--- a/typing-break/drw-break-window.c
+++ b/typing-break/drw-break-window.c
@@ -150,7 +150,11 @@ drw_break_window_init (DrwBreakWindow *w
 
 	screen = gdk_screen_get_default ();
 	display = gdk_screen_get_display (screen);
+#if GTK_CHECK_VERSION (3, 22, 0)
 	gdk_monitor_get_geometry (gdk_display_get_monitor (display, root_monitor), &monitor);
+#else
+	gdk_screen_get_monitor_geometry (screen, root_monitor, &monitor);
+#endif
 
 	gtk_window_set_default_size (GTK_WINDOW (window),
 				     WidthOfScreen (gdk_x11_screen_get_xscreen (screen)),