wikijs/client/graph/admin/mail/mail-query-config.gql

{
  mail {
    config {
      senderName
      senderEmail
      host
      port
      name
      secure
      verifySSL
      user
      pass
      useDKIM
      dkimDomainName
      dkimKeySelector
      dkimPrivateKey
    }
  }
}