Labyrinth 1.1: Making End-to-End Encrypted Backups Even More Reliable
May 11, 2026Emma Connor
Summary
Labyrinth 1.1 introduces a new sub-protocol for Messenger's end-to-end encrypted backups. This protocol allows messages to be sent directly to the recipient's encrypted backup as they are transmitted, rather than waiting for the device to come online. This enhances reliability by ensuring message survival even if a device is lost, switched, or experiences long gaps between sign-ins. The system wraps each message with an encryption key placed directly into the recipient's backup, making it unreadable by Meta.
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