Thank you for contacting us.
To make it work you will have to set the IsHeaderHitTestVisible
property of the RadWindow to True. In that way the Button in the Header will become clickable.
Hope this information is helpful. Please let us know if you have any other questions.
the Telerik team
Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items