&gt;  you simply verify the other party&#x27;s key once and then good to go<p>Against what, though?  The key that Whatsapp asserts is valid for the other user?<p>As far as I am aware there&#x27;s no way to access and visually eyeball-compare the raw keys in Whatsapp, just what the app presents as a signature or QR code.  Open to correction.