People will do what people can do. Test your email client for leakage and then plug the leaks. There is some discussion and links on stackexchange [1] If yo

People will do what people can do. Test your email client for leakage and then plug the leaks. There is some discussion and links on stackexchange [1] If your client can't plug the leaks on its own, please file a bug with the mail client developers. Please consider asking them politely to make those settings default. [1] - https://security.stackexchange.com/questions/23718/is-my-email-client-violating-my-privacy https://security.stackexchange.com/questions/23718/is-my-ema...