True if the chat is encrypted. This means that all messages in the chat are encrypted, and all contacts in the chat are "key-contacts", i.e. identified by the PGP key fingerprint.
False if the chat is unencrypted. This means that all messages in the chat are unencrypted, and all contacts in the chat are "address-contacts", i.e. identified by the email address. The UI should mark this chat e.g. with a mail-letter icon.
Unencrypted groups are called "ad-hoc groups" and the user can't add/remove members, create a QR invite code, or set an avatar. These options should therefore be disabled in the UI.
Note that it can happen that an encrypted chat contains unencrypted messages that were received in core <= v1.159.* and vice versa.
See also is_key_contact on Contact.
True if the chat is protected.
UI should display a green checkmark in the chat title, in the chat profile title and in the chatlist item if chat protection is enabled. UI should also display a green checkmark in the contact profile if 1:1 chat with this contact exists and is protected.
cheaper version of fullchat, omits:
used when you only need the basic metadata of a chat like type, name, profile picture