JSFiddle - React, Tailwind, and code Playground

HTML

<div id="contenedor">mouse</div>

JavaScript

function mundo(){
    alert("hola");
    
}
function hola(){
    alert("mundo");
    
}
window.onload=function(){
var aparecer=document.getElementById("contenedor");
    aparecer.addEventListener("mouseover", hola ,false);
    aparecer.addEventListener("click", mundo ,true );
}