diff --git a/scene/main/viewport.cpp b/scene/main/viewport.cpp
index 089f3b5d63..d19b5767c2 100644
--- a/scene/main/viewport.cpp
+++ b/scene/main/viewport.cpp
@@ -319,6 +319,7 @@ void Viewport::_notification(int p_what) {
 //				update_worlds();
 			}
 
+			add_to_group("_viewports");
 			if (get_tree()->is_debugging_collisions_hint()) {
 				//2D
 				Physics2DServer::get_singleton()->space_set_debug_contacts(find_world_2d()->get_space(),get_tree()->get_collision_debug_contact_count());