JSFiddle - React, Tailwind, and code Playground

JavaScript

/*-----------------------------------------------------
			global function for Set/Get Cookie
------------------------------------------------------*/
function setCookie(cname, cvalue, exdays) {
  var d = new Date();
  d.setTime(d.getTime() + (exdays * 24 * 60 * 60 * 1000));
  var expires = "expires=" + d.toGMTString();
  document.cookie = cname + "=" + cvalue + ";" + expires + ";path=/";
}

function getCookie(name) {
  var value = "; " + document.cookie;
  var parts = value.split("; " + name + "=");
  if (parts.length == 2) return parts.pop().split(";").shift();
}
//set cookie
setCookie("selectedUnit", "10", 365);
//get cookie
let cookieUnits = getCookie("selectedUnit");
console.log('cookieUnits-->' + cookieUnits);

//list all cookies
function listCookies() {
  var theCookies = document.cookie.split(';');
  var aString = '';
  for (var i = 1; i <= theCookies.length; i++) {
    aString += i + ' ' + theCookies[i - 1] + "\n";
  }
  return aString;
}
console.log(listCookies());