JSFiddle - React, Tailwind, and code Playground

HTML

<table id="tab" border=1>
    <tr>
        <td>A col1</td>
        <td>A col2</td>
    </tr>
</table>

JavaScript

console.log("Here!");
var table = document.getElementById("tab");
var trnew = document.createElement("tr");
trnew.id = "row" + 2;
var td1 = document.createElement("td");
td1.className = "r2col1";
var td2 = document.createElement("td");
td2.className = "r2col2";
trnew.appendChild(td1);
trnew.appendChild(td2);
table.appendChild(trnew);
console.log(table.outerHTML);