diff -ur gtk-sharp-2.12.45.org/sample/test/TestRange.cs gtk-sharp-2.12.45/sample/test/TestRange.cs
--- gtk-sharp-2.12.45.org/sample/test/TestRange.cs	2016-09-21 11:49:20.000000000 +0000
+++ gtk-sharp-2.12.45/sample/test/TestRange.cs	2020-02-04 16:55:49.527862899 +0000
@@ -9,6 +9,7 @@
 using System;
 
 using Gtk;
+using Range=Gtk.Range;
 
 namespace WidgetViewer {