OptionalblobId?: Id | nullOptionalcharset?: string | nullThe value of the charset parameter of the Content-Type header field, if present, or null if the header field is present but not of type "text/*"
Optionalcid?: string | nullThe value of the Content-Id header field of the part, if present; otherwise, it's null
Optionaldisposition?: string | nullThe value of the Content-Disposition header field of the part, if present; otherwise, it's null
Optionalheaders?: EmailHeader[]Optionallanguage?: string[] | nullThe list of language tags in the Content-Language header field of the part, if present
Optionallocation?: string | nullThe URI in the Content-Location header field of the part, if present
Optionalname?: string | nullOptionalpartId?: string | nullOptionalsize?: numberuint
OptionalsubParts?: EmailBodyPartFields[] | nullOptionaltype?: stringThe value of the Content-Type header field of the part, if present; otherwise, the implicit type as per the MIME standard ("text/plain" or "message/rfc822" if inside a "multipart/digest")
RFC 8621 (4.1.4) - https://datatracker.ietf.org/doc/html/rfc8621#section-4.1.4