win32 app window not shared/casted in debug

[sergyu91ma]

Here:
https://devblogs.microsoft.com/visualstudio/re-imagining-collaboration-for-visual-studio-with-
live-share-app-casting-and-contacts/
says that: App casting currently works for UWP, WinForms, Win32 C++ apps, C++ and CMake console apps with many more to come!

I tried to debug a C++ desktop win32 app but the window doesn't appears on the 'joined' side.
We are using VS 2019 16.5.2 both on Windows 10 1909 with LiveShare 1.0.1891.1 with insiders features ON.

What am i missing?

[Moniarchy]

Adding @jramsay.

[lostintangent]

Closing this as a duplicate of #236.