title: Element disappears after removing class
body: <p>I've come across some strange behavior in Chrome 60.0 when removing a class from an element with a very specific configuration.</p>
  
  <p>I removed the <code>fade</code> class from an <code>&lt;h1&gt;</code> element and it makes it completely disappear. The problem can be reproduced by removing the class in the dev-tools element inspector as well. Can anyone tell me what's going on here?</p>
  
  <p>The element should just go back to full opacity after clicking the button.</p>
  
  <p><img src="https://i.stack.imgur.com/FgJh3.gif" width="300"></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>var button = document.querySelector('button');
  var h1 = document.querySelector('h1');
  button.addEventListener('click', function(){
     h1.classList.remove('fade');
  });</code></pre>
  <pre class="snippet-code-css lang-css prettyprint-override"><code>.center {
    overflow: hidden;
  }
  h1 {
    float: left;
    overflow: hidden;
  }
  .fade {
    opacity: .2;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="center"&gt;
    &lt;div&gt;
      &lt;h1 class="fade"&gt;Watch me disappear&lt;/h1&gt;
    &lt;/div&gt;
  &lt;/div&gt;
  &lt;button&gt;Click&lt;/button&gt;</code></pre>
  </div>
  </div>
  </p>