Chromium browser now have a new feature that encrypts stored cookies by default by the browser. Google Chrome web browser also saves cookies to a database file in the user’s data folder. Google may soon adopt similar feature in the all official desktop versions of Chrome browser, that will encrypt the browser cookies with 128-bit AES encryption before saving to the hard disk. This encryption is at system user level i.e. This will only protect the cookies of a system user from the access by other users on the same system.
Source: https://thehackernews.com/2014/01/Chrome-encrypt-web-cookies-tool.html