wpf - Compiling pages with custom extension (for ex .custx) as if they were .xaml files in Visual Studio -

In a VS package (Visual Studio Extensibility) I have a custom extension registered with XamlLanguageService (formerly for ".custx")

However, when I compile it as "page" (buildaction), winfax target / compiler error with the following error message.

MySample \ Page1.custx: Error: The markup file is not valid. Specify a source markup file with a .xaml extension.

I am looking for a solution, so compile .custx pages as pages, just like WPML applications like .xaml pages

Any help is greatly appreciated

I just created the XML file extension There is no way to work around) Is there a reason that you need your file extension?