When trying to access phabricator via https://p.phcdn.net people are presented with an exception.
Message: "This Phabricator install is configured as "https://secure.phabricator.com/", but you are using the domain name "p.phcdn.net" to access a page which is trying to set a cookie. Acccess Phabricator on the configured primary domain or a configured alternate domain. Phabricator will not set cookies on other domains for security reasons."