Good point. Looks like google doesn't add these headers if you're using their web interface and apparently the majority of people I email with don't leak this e

Good point. Looks like google doesn't add these headers if you're using their web interface and apparently the majority of people I email with don't leak this either, however once I started looking there's a surprising amount of emails in my inbox that do. I'm now trying to remember if I deliberately disabled this when I set up our new mail server or not...