A simple function to parse a browser cookie string

cookie-deserializer.js

function deserialize(cookieString) {
  return cookieString
    .split('; ')
    .filter(Boolean)
    .reduce((acc, cur) => {
      const c = cur.match(/(^.*?)=(.*$)/);
      return { ...acc, [c[1]]: c[2] };
    }, {});
}

deserialize(document.cookie);