anchor.diff:      }
   
       if (_scenes.isEmpty) {
  -      //print("SceneManager.pushScene adding first scene: ${scene.tag}");
  +      //print("SceneManager.replaceScene adding ${scene} as first scene");
         _scenes.add(scene);
       } else {
         BaseNode firstScene = _scenes.removeFirst();
  -      //print("SceneManager.replaceScene replacing scene: ${scene.tag} over ${firstScene.tag}");
  +      //print("SceneManager.replaceScene replacing ${firstScene} with ${scene}");
         _scenes.addFirst(scene);
       }
   
       _nextScene = scene;
       sendCleanupToScene = true;
  +    //print("SceneManager.replaceScene " + this.toString());
     }
     
     /**
  
positive.code:    */
    void popToRootScene() {
      popToSceneStackLevel(TO_ROOT);
    }
    
    /**
  
negative.code:       sendCleanupToScene = true;
        
        BaseNode scene = _scenes.removeFirst();
        //print("SceneManager.popScene popped scene: ${scene}. Next scene is ${_scenes.first}");
        
        if (_scenes.isNotEmpty) {
          _nextScene = _scenes.first;
        }
      }
      //print("SceneManager.popScene " + this.toString());
    }
    
    /**
  