How does Ghost stop account sharing, if it does?

Thanks!

This aspect of this type of link functionality is not mentioned in the main Ghost Security help page where it might sit well, both to help finding the answer more easily and as an advert for how brilliant Ghost is!

Of note is a more commonplace and closely related point that is in fact addressed on that Security Page, but not very well. Thanks to @Cathy_Sarisky who has commented on the vulnerability recently (not the Security page).