DataTables - custom renderer

HTML

<link rel="stylesheet" href="https://cdn.datatables.net/1.11.3/css/jquery.dataTables.min.css">
<link rel="stylesheet" href="https://cdn.datatables.net/responsive/2.2.9/css/responsive.dataTables.min.css">
<script src="https://code.jquery.com/jquery-3.5.1.js"></script>
<script src="https://cdn.datatables.net/1.11.3/js/jquery.dataTables.min.js"></script>
<script src="https://cdn.datatables.net/responsive/2.2.9/js/dataTables.responsive.min.js"></script>
<h1>
  <a href="https://datatables.net/extensions/responsive/examples/child-rows/custom-renderer.html">
    datatables.net - responsive examples - child rows - custom renderer
  </a>
</h1>

<table id="example" class="display nowrap" style="width:100%">
  <thead>
    <tr>
      <th>First name</th>
      <th>Last name</th>
      <th>Position</th>
      <th>Office</th>
      <th>Age</th>
      <th>Start date</th>
      <th>Salary</th>
      <th>Extn.</th>
      <th>E-mail</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Tiger</td>
      <td>Nixon</td>
      <td>System Architect</td>
      <td>Edinburgh</td>
      <td>61</td>
      <td>2011/04/25</td>
      <td>$320,800</td>
      <td>5421</td>
      <td>[email protected]</td>
    </tr>
    <tr>
      <td>Garrett</td>
      <td>Winters</td>
      <td>Accountant</td>
      <td>Tokyo</td>
      <td>63</td>
      <td>2011/07/25</td>
      <td>$170,750</td>
      <td>8422</td>
      <td>[email protected]</td>
    </tr>
    <tr>
      <td>Ashton</td>
      <td>Cox</td>
      <td>Junior Technical Author</td>
      <td>San Francisco</td>
      <td>66</td>
      <td>2009/01/12</td>
      <td>$86,000</td>
      <td>1562</td>
      <td>[email protected]</td>
    </tr>
    <tr>
      <td>Cedric</td>
      <td>Kelly</td>
      <td>Senior Javascript Developer</td>
      <td>Edinburgh</td>
      <td>22</td>
      <td>2012/03/29</td>
      <td>$433,060</td>
      <td>6224</td>
      <td>[email protected]</td>
    </tr>
    <tr>
      <td>Airi</td>
     ...

JavaScript

$(document).ready(function() {
  $('#example').DataTable({
    responsive: {
      details: {
        renderer: function(api, rowIdx, columns) {
          let data = $.map(columns, function(col, i) {
            return col.hidden ?
              '<tr data-dt-row="' + col.rowIndex + '" data-dt-column="' + col.columnIndex + '">' +
              '<td>' + col.title + ':' + '</td> ' +
              '<td>' + col.data + '</td>' +
              '</tr>' :
              '';
          }).join('');

          return data ?
            $('<table/>').append(data) :
            false;
        }
      }
    }
  });
});