Please excuse me for the confusion with your name.
I saw that you post your question in a new Support Ticket (with ID:891760 ) and one of my colleagues (Peshito) answered it there. Please take a look at and see if its approach could be helpful for your scenario.
If this does not help, can you tell me what you mean by saying that the popup hides the shapes? Which shapes do you mean? The selected shape or all shapes in general? If you mean that the selected shape is hidden (as demonstrated in the "2_pop_opened.png
"). This behavior is expected if the position of the Popup is set close to the shape's bounds. In order to resolve this you can set bigger HorizontallOffset of the popup based on its size and the shape's size.
If you want the popup to be displayed behind the shapes, I am afraid this cannot be achieved with the Popup element, because in WPF the popup is always rendered above all other element.
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