Exceptions are occuring on ALL bindings, not just with RelativeSource Command="{Binding AddCommand}" will also raise an exception.
Won't Fix: The observed behavior is caused by a RadTabControl functionality that explicitly assigns the DataContext of the content area which is not needed for this scenario. If you set the PropagateItemDataContextToContent property of RadTabControl to False everything will work as expected. Regards, Kalin
The example is not correct. If we close inner tab control, and then close outer tab control, there are no exceptions. If we close outer tab control while inner tab control is still displayed, then we receive exceptions. Currently in my project I receive 30
Binding exceptions occure when wemoving TabControl from the visual tree. Example: if we have TabControl inside TabControl and remove the inner TabControl from the visual tree, a binding exception occurs.