@cmarcelo Your comment inspired me!

Let me give you my original thought on this PresentationDisplayManager. It is designed to act as a platform specific stuff which could enumerate all available displays connected to system, you might notice the EnsureInitialized method, at present it is left empty and will be filled up in future. The manager works on UI thread, and might be better to be a singleton and be created on demand since it is only needed when presentation extension is created (if the API extension is created on demand).

But now I prefer to treat it as a testing stuff since there is no platform specific code contained in it.