Готовые методы работы с куками на javaScript.
function getCookies(cookieName) { let cookie = {}; document.cookie.split(';').forEach(function(el) { let [key,value] = el.split('='); cookie[key.trim()] = value; }); return cookie[cookieName]; } function clearSpecificCokieByName(name) { // document.cookie = name +'=; Path=/; Expires=Thu, 01 Jan 1970 00:00:01 GMT;'; document.cookie = name +'=; Expires=Thu, 01 Jan 1970 00:00:01 GMT;'; }