”selfClosingTags“ not work

[missannil]

import serialize from "dom-serializer";
import { parseDocument } from "htmlparser2";
  const html = `
                      <div class="container">
		                    <foo  />
                      </div >`;  
                   
  const result = serialize(parseDocument(html), { selfClosingTags: true, xmlMode: true})
  
  // result =   `<div class="container">
  //              <foo>
  //             </foo></div>`
  
  // expect  `<div class="container">
  //               <foo />
  //             </div>`
 

I don't get what I expect. What configuration error did I make?

[MickL]

Does it actually matter for the end result if the tag is self closing or not?