title: NSAlert duplicates "help" menu
body: <p>I have a very simple modal code in my project:</p>
  
  <pre><code>/*!
   * @method      popUpDialog:
   * @abstract    Triggers a pop-up window.
   */
  - (void)popUpDialog:(NSString *)prompt {
      NSAlert * alert = [[[NSAlert alloc] init] autorelease];
      [alert setAlertStyle:NSInformationalAlertStyle];
      [alert setMessageText:@"Message"];
      [alert setInformativeText:prompt];
      [alert runModal];
  }
  </code></pre>
  
  <p>I am using this in the <code>- (NSPersistentStoreCoordinator *)persistentStoreCoordinator;</code> method to warn the users the migration was successful. Then it duplicates the help menu. It seems to be happening only with Mavericks. My app works in Snow Leopard just fine.</p>
  
  <p><img src="https://i.stack.imgur.com/G55ht.png" alt="Doubled help"></p>
  
  <p>Any ideas why that happens?</p>
  
  <p>Sorry, I couldn't find anything similar at Stack Overflow. I tested and it only happens if the message is displayed, so I think this code is the culprit.</p>
  
  <p>Thanks!</p>