diff --git a/Polyhedron/demo/Polyhedron/Polyhedron_demo_triangulate_facets_plugin.cpp b/Polyhedron/demo/Polyhedron/Polyhedron_demo_triangulate_facets_plugin.cpp
index 55db648ec36..99e8dc370f3 100644
--- a/Polyhedron/demo/Polyhedron/Polyhedron_demo_triangulate_facets_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Polyhedron_demo_triangulate_facets_plugin.cpp
@@ -42,7 +42,11 @@ public:
   }
 
   bool applicable() const { 
-    return qobject_cast<Scene_polyhedron_item*>(scene->item(scene->mainSelectionIndex()));
+    Q_FOREACH(Scene_interface::Item_id index, scene->selectionIndices())  {
+      Scene_polyhedron_item* item = qobject_cast<Scene_polyhedron_item*>(scene->item(index));
+      if(!item) return false;
+    }
+    return true;
   }