It was still called Facebook Messenger and Meta was still owned by Facebook when Messenger launched end-to-end encrypted (E2EE) talking in 2016. The optional function, which allows users to encrypt text messages as well as group chats and calls, has now been fully implemented and is available to everyone. Meta has considered the possibility of moving to E2EE as the default, but that may not happen until next year at the earliest, due to concerns that doing so would jeopardise public safety, which some regulators disagree with.
The secure conversations are accessible in two ways: either through vanish mode, which is accessed by swiping up on a current chat to enter one where messages are automatically deleted when the window is closed, or through the original Secret Conversations feature, which was released in 2016. When you start a new chat, you can enable this feature by toggling the lock icon.
The functionality will be fully implemented, but there will also be some new features available to use. GIFs, stickers, emotions, and long-pressing to reply or forward messages are now available in end-to-end encrypted chats. It is also possible to identify real accounts (as long as they are not Elon Musk) in the encrypted chats, thanks to the addition of verified badges.
A screenshot notice in the style of Snapchat will be rolled out gradually over the next several weeks, and you may also preserve any media that has been exchanged in the chat room.