File _service of Package claws-mail-3.18.0-gtk3

<services>
  <service name="download_url">
    <param name="host">www.claws-mail.org</param>
    <param name="protocol">https</param>
    <param name="path">//releases/claws-mail-3.18.0.tar.xz</param>
  </service>
</services>