File spotify.xml of Package Spotify-client

<?xml version="1.0" encoding="utf-8"?>
<service>
  <short>Spotify Connect</short>
  <description>Listen on your speakers or TV, using the Spotify app as a remote. Sync local playlists across devices.</description>
  <port protocol="tcp" port="57621-57622"/>
  <port protocol="udp" port="57621-57622"/>
</service>