> Websites will just add a CNAME entry that points to whatever service they were using before. Then it's a second party (subdomain) cookie. That doesn't cause

> Websites will just add a CNAME entry that points to whatever service they were using before. Then it's a second party (subdomain) cookie. That doesn't cause the same problem as a third-party cookie, because it's not shared with other services that use the same third party. A subdomain doesn't let you get tracked across other sites.