title: Xcode 4 missing drop down lists in Build Settings
body: <p>I'm using Xcode 4 and in Build Settings all drop down lists have gone away.</p>
  
  <p>Instead of the drop down lists, I have text boxes.</p>
  
  <p>See this image, for example:</p>
  
  <p><img src="https://i.stack.imgur.com/4NOO6.png" alt="enter image description here"></p>
  
  <p>I'm totally puzzled: how can I enable drop down lists again?</p>