> There's just no way, in real life, for Facebook to add what you're describing to one of the most prominent messaging apps in the world without somebody notici

> There's just no way, in real life, for Facebook to add what you're describing to one of the most prominent messaging apps in the world without somebody noticing Your point moved from "key transparency is the defense" to "someone will notice". But if your defense is the hope of "someone noticing" you're in for a big surprise. Sometimes things go unnoticed. Look no further than OpenSSL, open source, used by billions, deployed by companies worth as much as small countries, and yet nobody noticed Heartbleed for years. So I'll be very cynical that some development flag targeting a handful of people in an app like WhatsApp and then is removed will be so noticeable that it's a strong defense.