Create a key

In Configurações → Criptografia (Settings → Encryption), create a key for the account. There are three types:

• Curve25519: fast, small and accepted by most programs. It is the recommended one.
• RSA 4096: for people who exchange email with older programs.
• Post-quantum (experimental): ML-KEM-768 with X25519. Few programs can read it yet.

Back it up

Without a backup, a lost computer takes the key with it, and the messages encrypted to it can no longer be opened. Use the password-protected backup and keep the file off the computer.