title: Make textarea with setted height grow when new line is added
body: <p>I have a <code>textarea</code> with a fix <code>height</code> of <code>70px</code>. When I press enter for a new line multiple times I would like to let the <code>height</code> of the <code>textarea</code> grow. At the moment, after the 6th line a scrollbar appears. This makes sense, because of the fix <code>height</code> of <code>70px</code>. But is there a way to solve this?</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-css lang-css prettyprint-override"><code>textarea {
    min-height: 70px;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;textarea&gt;Hello World! Click "enter" for more lines...&lt;/textarea&gt;</code></pre>
  </div>
  </div>
  </p>