title: why document has getElementById method even though it doesnt inherit from Element?
body: <p>Following the MDN docs, the <a href="https://developer.mozilla.org/en-US/docs/Web/API/Element" rel="nofollow noreferrer">Element interface</a> holds all methods to search for dom nodes like</p>
  
  <ul>
  <li>getElementById</li>
  <li>getElementsByTagName</li>
  <li>...</li>
  </ul>
  
  <p>MDN also <a href="https://developer.mozilla.org/de/docs/Web/API/Document" rel="nofollow noreferrer">states</a> that Document inherits directly from Node. <strong>NOT</strong> from Element.</p>
  
  <p>So why does Document hold all these Element methods (and methods from the ParentNode interface)?
  Is MDN just not up to date with the specs or am I missing something?</p>