Shared project: Object reference not set to an instance of an object.

When a resw is in a shared project (I'm using Uno Platform to target both Wasm and UWP so I need it like that) then it throws a NullReferenceException when you try to generate code.

Also huge thanks for providing this extension @rudyhuyn ! Quite baffling actually that VS does not do this out of the box like with WPF!