Meta is rolling out end-to-end encryption (E2EE) as the default setting for personal conversations on Messenger. This milestone reflects the company’s commitment to ensuring that only the sender and intended recipients can access personal messages and that messages are authentic. The journey to bring E2EE to Messenger has been complex, involving the rebuilding of application protocols to enhance privacy, security, and safety while maintaining popular features. Meta’s approach to E2EE encompasses concepts such as confidentiality in transit and storage, control over endpoints, private feature designs, logging limitations, application security, being deliberate about what’s being protected, and third-party scrutiny. Although E2EE is now available for personal conversations, testing continues for group messaging and Instagram Direct Messages.
https://engineering.fb.com/2023/12/06/security/building-end-to-end-security-for-messenger/