Yes, I managed to reproduce this and indeed the parent of the ListBoxItem is null. Surely, I did not expect that!
I can offer several workarounds:
1. Use a more verbose payload: The payload will be a class that will hold both the item and its parent. On DragQuery the item will create the Payload and add itself. Then its parent (the ListBox) will also handle the event and will add itself too.
2. Handle the DragInfo event on the ListBox in its DragStatus.DragComplete
phase, then the ListBox can check if the Destination of the drop is the recycle bin and then remove the item accordingly.
Hopefully this will work in your case,
the Telerik team
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