title: Enter responsive design mode missing
body: <p>I just upgraded safari to version 9.0.3, one of my parners in another city reproduced an error on my website using responsive desing mode and iOS 9.1 iPhone user agent in a MacBook (OSX 10.9.5).</p>
  
  <p>They were explaining me how to reproduce the issue by using the "Enter responsive design mode" in the develop tab but no matter what I do, that specific option never shows up. I already disabled all extensions and deleted my preferences (not sure if this helps). I tried the option + command + R shortcut but it doesn't do anything neither. I already tried reseting safari and restarted several times.</p>
  
  <p>Where did this feature go?</p>
  
  <p>Edit: added screenshot:
  <img src="https://i.imgur.com/GnhRgcM.png" alt="screenshot"></p>
  
  <p>Edit: 2nd screenshot:
  <img src="https://i.imgur.com/hPsmNvD.png" alt="screenshot02"></p>