Question about postopen event on a page

So I’m using the postopen event on a page to trigger an action, which works fine. But I notice that the Postopen event sets up with ‘Source as NotesUIDocument’ just like in a document. But what is returned for source when it is a page? You can’t have a handle to a page, can you?

Subject: Question about postopen event on a page

Oh, yes you can. Almost everything in Notes is a document – design notes as well as data notes – and Pages and Forms are no exception.