title: How can I create an editable combo box in HTML/Javascript?
body: <p>I need to let users select an item from a dropdown list, but also allow them to instead enter any text, even if it doesn't match an item in the list. How can I achieve this on a web page with HTML and Javascript?</p>
  
  <p>The <code>select</code> field doesn't let users enter text, and the <code>input</code> text field doesn't show the preferred alternatives.</p>
  
  <p>All items must show if the user opens the dropdown, so it can't be a simple auto-complete that only shows matching items.</p>