JSFiddle - React, Tailwind, and code Playground

by ukkpower

HTML

<a href="http://www.microsoft.com">Click here to navigate to 
      www.microsoft.com</a>

JavaScript

function closeIt()
{
  return "Any string value here forces a dialog box to \n" + 
         "appear before closing the window.";
}
window.onbeforeunload = closeIt;