JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="inputText"></textarea>
<button id="doIt">do it</button>

<h3>result</h3>
<code id="output"></code>

CSS

code {
    display:block;
    padding: 4px;
    background-color: #EFEFEF;
    
}

JavaScript

$('#doIt').click(function () {
    var encodedStr = $('#inputText').val().replace(/[\u00A0-\u9999<>\&]/gim, function(i) {
       return '&#'+i.charCodeAt(0)+';';
    });
    $('#output').html(encodedStr.replace(/&/gim, '&amp;'));
});