Comment by RajT88

Facebook messenger similarly claims to be end to end encrypted, and yet if it thinks you are sending a link to a pirate site, it "fails to send". I imagine there are a great many blacklisted sites which they shadow block, despite "not being able to read your messages".

My pet conspiracy theory is that the "backup code" which "restores" encrypted messages is there to annoy you into installing the app instead of chatting on the web.