Rémi Bernon (@rbernon) commented about include/windows.devices.bluetooth.rfcomm.idl:
- [
 contract(Windows.Foundation.UniversalApiContract, 1.0),exclusiveto(Windows.Devices.Bluetooth.Rfcomm.RfcommDeviceService),uuid(a4a149ef-626d-41ac-b253-87ac5c27e28a)- ]
 - interface IRfcommDeviceServiceStatics : IInspectable
 - {
 HRESULT FromIdAsync([in] HSTRING id, [out, retval] Windows.Foundation.IAsyncOperation<Windows.Devices.Bluetooth.Rfcomm.RfcommDeviceService *> **operation);HRESULT GetDeviceSelector([in] Windows.Devices.Bluetooth.Rfcomm.RfcommServiceId *id, [out] [retval] HSTRING *selector);- }
 - [
 contract(Windows.Foundation.UniversalApiContract, 1.0),marshaling_behavior(agile),static(Windows.Devices.Bluetooth.Rfcomm.IRfcommDeviceServiceStatics, Windows.Foundation.UniversalApiContract, 1.0),
```suggestion:-0+0 static(Windows.Devices.Bluetooth.Rfcomm.IRfcommDeviceServiceStatics, Windows.Foundation.UniversalApiContract, 1.0), static(Windows.Devices.Bluetooth.Rfcomm.IRfcommDeviceServiceStatics2, Windows.Foundation.UniversalApiContract, 3.0), ```
With the proper forward declaration for the interface above, you don't need to define it if you don't intend to implement it.