JSFiddle - React, Tailwind, and code Playground

HTML

<textarea></textarea>

<textarea></textarea><textarea></textarea><textarea></textarea><textarea></textarea><textarea></textarea><textarea></textarea><textarea></textarea><textarea></textarea>

JavaScript

window.onbeforeunload = exit;
function exit() {
var t = 0;
$("textarea").each( function() {
var v = $(this).val();
if(v!="") {
t=t+1;
}
});
if(t>=1) {
return "You Have Some text written in textareas. Still you want to leave?";
}
}