title: Safari is not acknowledging the "required" attribute. How to fix it?
body: <pre class="lang-html prettyprint-override"><code>&lt;form id="customerForm"&gt;
      &lt;label&gt;
          First Name:
          &lt;input id="firstName" required /&gt;
      &lt;/label&gt;
      &lt;label&gt;
          Social Security Number:
          &lt;input id="ssn" required pattern="^d{3}-d{2}-d{4}$"
              title="Expected pattern is ###-##-####" /&gt;
      &lt;/label&gt;
      &lt;input type="submit" /&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>When I try that document in Chrome, it accepts the conditions and shows the error, as expected.</p>
  
  <p>But when I try that document in Safari, it shows no error.</p>