I have tried to create a simple project (attached), but I am not completely sure this is the exact solution that you need. Can you, please share more details of your scenario or a simple project? What I have done in my project is creating a RadDocking with two PaneGroups each with two Panes. When a pane is not pinned and you click on the header or just hover the mouse a message box is displayed.
I hope the attached project is helpful.
All the best,
the Telerik team
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