A few maybe-not-so-nefarious options I can think of: a) some kind of third-party OAuth sign in library that may not be properly configured? Is it possible to l

A few maybe-not-so-nefarious options I can think of: a) some kind of third-party OAuth sign in library that may not be properly configured? Is it possible to log in the website using some kind of single-sign in? b) requesting favicons to use as a visual icon when displaying/categorizing transactions? c) some external user tracking package that could be used for analytics or support?