Problem removing UndoManager in GraphLinksModel


I want to remove the UndoManager becuase i don't need the ability of undo and I want to save memeory.

but when I set:

model.HasUndoManager = false;

the control don't behave good.

This problem reproduces in the goWPF demo in the FlowGrammer when I change the HasUndoManager  from true to false.
When I add a new node it looks like 

Only after resizing the window it looks ok<o:p></o:p>
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Can you tell me how can I remove the undo manager and keep the control working properly?<o:p></o:p>
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That’s interesting. I wonder why no one has reported that before.

You can avoid this problem by using your own UndoManager that doesn’t record any Changed events:

public class CustomUndoManager : UndoManager {
protected override bool SkipEvent(ModelChangedEventArgs evt) { return true; }

and then replace:
model.HasUndoManager = true;
model.UndoManager = new CustomUndoManager();