http://protonmailrmez3lotccipshtkleegetolb73fuirgj7r4o4vfu7ozyd.onion/support/mail/contacts/contacts-encryption
Support Proton Mail Contacts Contacts encryption How to manually select trusted keys You can select which PGP key to use when sending emails to a trusted contact. This is also know as key pinning. Support Proton Mail Contacts Contacts encryption Address verification with trusted keys Use trusted encryption keys to specify which keys should be used to encrypt messages to each contact and verify their identity.