Which HTTP server? the getFavicon method requests the favicon from each domain, so any one email provider only gets a single request for a favicon. It doesn't send all the contact info to any single server.

So reading the code, say you have in your contact

[email protected] [email protected] [email protected]

The code makes a single request to acme.com (to get the favicon) and one to support.google.com to get that favicon (there's a special case for google to avoid getting the new doodle of the day). That's it.

I don't really see how that's sharing contact details.