╭considering: domain=$domain/sender_domain=$sender_address_domain
├──expanding: domain=$domain/sender_domain=$sender_address_domain
╰─────result: domain=recipient.domain/sender_domain=sender.domain
╭considering: domain=$domain/sender_domain=$sender_address_domain
├──expanding: domain=$domain/sender_domain=$sender_address_domain
╰─────result: domain=recipient.domain/sender_domain=sender.domain