A DESCRIPTION OF THE PROBLEM :
A null pointer exception occurs on the ScenePulseListener when iterating through the dirty node list:

for (int i = 0 ; i < dirtyNodesSize; ++i) {
  Node node = dirtyNodes[i];
  dirtyNodes[i] = null;
  if (node.getScene() == Scene.this) node.syncPeer();
}

A null check is needed on the node before calling node.getScene()

Note: this bug was previously reported on JDK 8 and marked as fixed:
https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8095034

The latest code does not preform this check.

The original bug mentions that this is a symptom and not a cause, but there does not appear to be any way to determine the cause in this case.

In some cases, this happens so frequently that the application locks up and the end user needs to restart. I have downloaded the JFX project from git hub and manually patched which solves the problem.

A one line fix would be greatly appreciated (and/or an explanation of what the cause could be).


CUSTOMER SUBMITTED WORKAROUND :
I have manually downloaded the GITHub project and added the NPE check. This fixes the issue.

FREQUENCY : occasionally