Thank you very much for the feedback.
I can agree that this behavior is not expected and have already introduced a fix for it which will be available with our next internal build on Monday (28.10). As a thank you for your help in addressing this issue, I've awarded you with some Telerik points.
Please let me know once you manage to test this out. I will be awaiting your reply.
Want to extend the target reach of your WPF applications, leveraging iOS, Android, and UWP? Try UI for Xamarin
, a suite of polished and feature-rich components for the Xamarin framework, which allow you to write beautiful native mobile apps using a single shared C# codebase.