title: Contextual help in Xcode not showing
body: <p>I'm trying to use 'Option-click' to see inline documentation in xcode. Here's what I get when I Option-click 'hasPrefix()':</p>
  
  <p><a href="https://i.stack.imgur.com/viWXQ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/viWXQ.png" alt=""></a></p>
  
  <p>Here's what I'm supposed to get:</p>
  
  <p><a href="https://i.stack.imgur.com/ULCFH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ULCFH.png" alt="enter image description here"></a></p>
  
  <p>How to fix? I've tried installing the command line tools from dev.apple site.</p>
  
  <p>xcode 10.0 / swift 4</p>