JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="paste_area"></textarea>
<div id="notice">No Info</div>

JavaScript

document.getElementById('paste_area').addEventListener('input', function() {
    let inArea = document.getElementById('paste_area').value;
    document.getElementById('notice').innerHTML='Text change: ' + inArea;
    alert(inArea);

});