JSFiddle - React, Tailwind, and code Playground

by WhetDawg

HTML

<table>
<thead>
  <tr>
    <th>Col 1</th>
    <th>Col 2</th>
    <th>Col 3</th>
  </tr>
</thead>
</table>

JavaScript

let $tbl = $('table');
let $ths = $('thead tr th',$tbl);
let $th = $ths.eq(0);

$th.before(`<th data-type='#' class='center'>#</th>`);