Drag and Drop: Cannot read property 'parentNode' of undefined

[web265p3]

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Current behavior
Navigate to: http://www.primefaces.org/primeng/#/dragdrop

Open the console and Drag & Drop an item in the "HEADER!!" of the Table. There is JS Error in showing up in the console. Everything works, but the error is clearly there. Just wanted to mention this behavior here. :)