How to create a KeyEventArgs object in WPF ( related to a SO answer )

phewwww

I’ve found it: Keyboard.PrimaryDevice.ActiveSource has to be used

InputManager.Current.ProcessInput(
    new KeyEventArgs(Keyboard.PrimaryDevice,
        Keyboard.PrimaryDevice.ActiveSource,
        0, Key.Tab)
    {
       RoutedEvent = Keyboard.KeyDownEvent
    }
);