The WPF extension releases 1.0 - 1.4 are deprecated and no new development will be actioned. All new features and functionality for the support of WPF are now handled instead by the .NET XAML extension using the com.castsoftware.wpf extension ID. Please see the section of documentation entitled Existing extensions for WPF and Silverlight for more information about the .NET XAML extension and the impacts of moving to it.