Determine the Scene that is selected when using context menu

I have a context menu that is used to create a game object.

If I select a game object in the scene hierarchy and access the context menu I get a valid MenuCommand.context.

If I select a scene in the hierarchy and access the context menu the MenuCommand.context is null.

The same goes for Selection.activeContext, Selection.activeObject, etc.

However, if I call new GameObject() then it is created in the selected scene.

How does new GameObject() get the selected scene?

 [UnityEditor.MenuItem( "GameObject/MyGameObject", false, 10 )]
 static void CreateMyGameObject( UnityEditor.MenuCommand menuCommand )
 {
      var parent = menuCommand.context;  // <-- null
      var activeContext = UnityEditor.Selection.activeContext // <-- null
      var activeContext = UnityEditor.Selection.activeObject // <-- null
      var activeScene = SceneManager.activeScene // <-- not necessarily the selected scene
      var realScene = new GameObject().scene; // <-- the scene that was selected in the hierarchy!
 }