title: Safari: focus event doesn't work on button element
body: <p>The focus event works fine on all browsers but Safari when it has been clicked.</p>
  
  <p>And it works fine on div[tabindex] element, but don't work on button or input:button element.</p>
  
  <p>It also can get the focus event when I use $('.btn').focus().</p>
  
  <p>Why does the focus event haven't triggered on click ?</p>
  
  <p>Here is my code:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>$(".btn").focus(function (e) {
   $(".result").append("&lt;p&gt;Event:"+e.type+", target:"+e.target+"&lt;/p&gt;");
  })</code></pre>
  <pre class="snippet-code-css lang-css prettyprint-override"><code>.result{min-height:200px;border:1px solid #000;}</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"&gt;&lt;/script&gt;
  &lt;button class="btn"&gt;button 1&lt;/button&gt;
  &lt;input type="button" class="btn" value="button 2"/&gt;
  &lt;div class="btn" tabindex="0"&gt;div element&lt;/div&gt;
  &lt;h1&gt;
  Result:
  &lt;/h1&gt;
  &lt;div class="result"&gt;
  
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>