title: Plug-in that "knows" the current open document?
body: <p>I want to build a plug-in that gets loaded when the Notes client (8.5.2++) loads that gets called whenever a document is opened and get the (Notes) URL of that document. What extension points and APIs do I need?</p>
  
  <p><strong>Clarification</strong>:<br />
  I do know how to get to the current document (NotesUIWorkspace.currentDocument). What I don't know is how (and when) to register a listener to get notified.<br />
  <strong>Special challenge</strong>: documents can be opened in Framesets (more than one) and documents can be opened as part of a composite page. The Frameset isn't a big concern, but the composite. If this would require to listen to any page opening and inspect it - I'm fine with that</p>