JSFiddle - React, Tailwind, and code Playground

HTML

<img id="myimg" height="300" width="300" src="http://www.ricoh.com/r_dc/r/r8/img/sample_10.jpg" />

JavaScript

var myimg = document.getElementById('myimg');
var new_node = document.createElement("p");
new_node.innerHTML = "This is my Caption!";
myimg.parentNode.insertBefore(new_node,myimg.nextSibling);