JSFiddle - React, Tailwind, and code Playground

HTML

<table id="someTable">
    <thead>
        <tr>
            <th>Col1</th>
            <th>Col2</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>Value 1</td>
            <td>Value 2</td>
        </tr>
    </tbody>
</table>

<button id="newrow">+</button>

JavaScript

$(document).ready(function()
                  {
                      var table = $('#someTable'), 
                          newRow = '<tr><td>New Row Val</td><td>New Row Val</td></tr>';
                     $('#newrow').on('click', function(e)
                                     {
                                         table.find('tbody').append(newRow);
                                     });
                  });