JSFiddle - React, Tailwind, and code Playground

HTML

<button id="uno">uno</button>
<button id="dos">dos</button>

JavaScript

var uno=document.getElementById("uno");
var dos=document.getElementById("dos");
uno.onclick = function() {
    uno.innerHTML='esperando...';
    dos.onclick = function() {
         uno.innerHTML=dos.innerHTML; return false;
    }   
}