Adorner being calculated incorrectly using ListBox with Grouping and WrapPanel as ItemsPanel

[GallinaceUs]

What steps will reproduce this issue?

Using the default Showcase application, I modified the ListBox/Grouping sample to use a WrapPanel as ItemsPanel into the ListBox.
I also added dd:DragDrop.ItemsPanelOrientation="Horizontal" so the adorner is vertical.

Observed

By dragging an item at the end of a group, the Adorner does not positions correctly.
It gets even worst if you reduce the width of the ListBox so the wrapping actually occurs.

Here is a GIF for demonstration

Expected

The adorner should positions at the end of the group.

Environment

• GongSolutions.WPF.DragDrop v2.2.0
• Windows OS 10
• Visual Studio 2017/2019
• .NET Framework 4.7.2

Repository for reproducing

https://github.com/GallinaceUs/gong-wpf-dragdrop