title: How to access host element from within the shadow root using Shadow DOM v1?
body: <p>Given an element contained in a shadow root, how can I get to the element that hosts the said shadow root? Is there a single way to accomplish this regardless of where an element is in the tree (i.e. given a reference to either <code>element2</code> or <code>element3</code>, get the reference to <code>element1</code>)?</p>
  
  <pre><code>element1
  └ #shadow-root
    └ element2
      └ element3
  </code></pre>