JSFiddle - React, Tailwind, and code Playground

HTML

<pre id="res"></pre>

JavaScript

function x(){
  res.innerHTML += "function x called\n";
  res.innerHTML += "Letting setTimeout call y asynchronousely\n";
  setTimeout(function y(){
    res.innerHTML += "function y called\n";
  },0);
  res.innerHTML += "returning from x\n";
}
res.innerHTML += "Calling x\n";
x();