[Select] What to do with selectedcontent when multiple select is set with size 1

I think this might be an interesting topic to discuss in the (near?) future.

I was wondering how a <selectedcontent> should behave when multiple select is set with a size="1"

<select multiple size="1">
  <button>
    <selectedcontent></selectedcontent>
  </button>
  <option>option</option>
  <option>option 2</option>
  <option>option 3</option>
</select>

I like the idea of it outputting every selected option right after each other instead of 2 selected, 3 selected when more than 1 item is selected.

I would not foresee any comma separation for this, as this can probably easily be customized with pseudo-elements.

<select multiple size="1">
  <button>
    <selectedcontent></selectedcontent>
  </button>
  <option><div class="wrapper">option</div></option>
  <option><div class="wrapper">option2</div></option>
  <option><div class="wrapper">option3</div></option>
</select>

selectedcontent .wrapper::after {
  content: ',';
}

I thought this was a good idea, but other suggestions are more than welcome. It should at least be looked into.

Start by reviewing the issue's 20-comment discussion and the provided multiple select size="1" examples. This is a standards-design question rather than a named code change; done would mean reaching agreement on how selectedcontent should represent multiple selected options.