modules/graphics/src/main/java/javafx/scene/Parent.java

*** 495,505 ****
                      }
                      if (old.getParent() == Parent.this) {
                          old.setParent(null);
                          old.setScenes(null, null);
                      }
!                     if (!removedChildrenOptimizationDisabled) {
                          removed.add(old);
                      }
                  }
              }
          }
--- 495,508 ----
                      }
                      if (old.getParent() == Parent.this) {
                          old.setParent(null);
                          old.setScenes(null, null);
                      }
!                     // Do not add parent with null scene to the removed list.
!                     // It will not be processed in the list and its memory
!                     // will not be freed.
!                     if (scene != null && !removedChildrenOptimizationDisabled) {
                          removed.add(old);
                      }
                  }
              }
          }
*** 644,660 ****
--- 647,671 ----
                  childrenTriggerPermutation = false;
              }
          }
      }
  
+     // This method is to do cleanup on parent when it is removed from a scene 
+     private void nullSceneCleanup() {
+         if (removed != null) {
+             removed.clear();
+         }
+     }
+ 
      @Override
      void scenesChanged(final Scene newScene, final SubScene newSubScene,
                         final Scene oldScene, final SubScene oldSubScene) {
  
          if (oldScene != null && newScene == null) {
              // RT-34863 - clean up CSS cache when Parent is removed from scene-graph
              StyleManager.getInstance().forget(this);
+             nullSceneCleanup();
          }
  
          for (int i=0; i<children.size(); i++) {
              children.get(i).setScenes(newScene, newSubScene);
          }