title: ES6 classes don't work on Chrome 47
body: <p>Google Chrome claims to support ES6 classes since version 42, but it gives <code>Uncaught SyntaxError: Unexpected token class(…)</code> when i run the simple code from below in the console:</p>
  
  <pre><code>class Polygon {
    constructor(height, width) {
      this.name = 'Polygon';
      this.height = height;
      this.width = width;
    }
  </code></pre>
  
  <p>Firefox also doesn't work. Microsoft Edge works just fine. Is this normal?</p>