title: Why is GPU frame capture not working with Metal?
body: <p>When I click on the camera button to capture and debug the GPU, it just disables the button and nothing else happens. When I then <em>stop</em> the app from XCode, the view is (confusingly) switched to Assistant editor, with source code in both views.</p>
  
  <p>Also, I noticed the FPS stays at zero in the debug panel, while I can see video rendered from Metal shaders.</p>
  
  <p>If I run a new example app the GPU debugging works and I can see the FPS at 60. Does anyone know what it could be?</p>
  
  <p>Using Xcode 6.4 and iPhone 6.</p>