title: CSS data attribute new line character & pseudo-element content value
body: <p>Is it possible to have a new line in a data attribute ?</p>
  
  <p>I am trying to do something like this:</p>
  
  <p>CSS:</p>
  
  <pre class="lang-css prettyprint-override"><code>[data-foo]:after {
      content: attr(data-foo);
      background-color: black;
  }
  </code></pre>
  
  <p>HTML</p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;div data-foo="First line \a Second Line"&gt;foo&lt;/div&gt;
  </code></pre>
  
  <p>I found that "\a" is a new line in CSS, but still does not work for me.</p>