JSFiddle - React, Tailwind, and code Playground

HTML

<div id="affiche_cookie">
Texte de depart
</div>

JavaScript

function setCookie(cname, cvalue, nbsecondes) {
  var d = new Date();
  d.setTime(d.getTime() + (nbsecondes*1000));
  var expires = "expires="+ d.toUTCString();
  document.cookie = cname + "=" + cvalue + ";" + expires + ";path=/";
}

function getCookie(cname) {
  var name = cname + "=";
  var decodedCookie = decodeURIComponent(document.cookie);
  var ca = decodedCookie.split(';');
  for(var i = 0; i <ca.length; i++) {
    var c = ca[i];
    while (c.charAt(0) == ' ') {
      c = c.substring(1);
    }
    if (c.indexOf(name) == 0) {
      return c.substring(name.length, c.length);
    }
  }
  return "";
}

if(getCookie("nom")!="")
{
	console.log("le cookie existe");
	document.getElementById("affiche_cookie").innerHTML=getCookie("nom");
}
else //le cookie n'existe pas
{
	setTimeout(function(){
  //on crée le cookie.
  console.log("le cookie n'existe pas");
	setCookie("nom", "valeur", 3);
  //on rafraichit la page
  location.reload(true);
  }, 10000); 
  
}