title: window.outerWidth is 0 in Safari on iOS 10 beta
body: <p>Using an iPad with iOS 10 installed, I entered <code>window.outerWidth</code> in the browser console and got a value of <code>0</code>. OTOH, <code>window.innerWidth</code> correctly produced <code>1024</code> (landscape mode).</p>
  
  <p>In iOS 9, <code>window.outerWidth</code> correctly produced <code>1024</code>, so is this just a bug in the iOS 10 beta or is there a subtlety to this property that I'm missing?</p>