gecko-dev/themes/classic/messenger/contents.rdf

<?xml version="1.0"?>

<RDF:RDF xmlns:RDF="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
         xmlns:chrome="http://www.mozilla.org/rdf/chrome#">

  <!-- List all the skins being supplied by this theme -->
  <RDF:Seq about="urn:mozilla:skin:root">
    <RDF:li resource="urn:mozilla:skin:classic/1.0" />
  </RDF:Seq>

  <!-- classic Information -->
  <RDF:Description about="urn:mozilla:skin:classic/1.0">
    <chrome:packages>
      <RDF:Seq about="urn:mozilla:skin:classic/1.0:packages">
        <RDF:li resource="urn:mozilla:skin:classic/1.0:messenger"/>
      </RDF:Seq>
    </chrome:packages>
  </RDF:Description>

  <!-- Version Information.  State that we work only with major version 1 of this
       package. -->
  <RDF:Description about="urn:mozilla:skin:classic/1.0:messenger"
    chrome:skinVersion="1"/>
</RDF:RDF>