JSFiddle - React, Tailwind, and code Playground

HTML

<table>
  <tr>
    <td class="X">0</td>
  </tr>
  <tr>
    <td class="X">0</td>
  </tr>
</table>

JavaScript

var els = document.getElementsByClassName("X");

for (var i = 0; i < els.length; i++) {
  els[i].innerHTML = '2';
}