install.rdf

<?xml version="1.0"?>

<RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
     xmlns:em="http://www.mozilla.org/2004/em-rdf#">

  <Description about="urn:mozilla:install-manifest">
    <!-- shortnameofaddon@firstname.lastname -->
    <em:id>react@david.nz</em:id>
    <!-- full name of addon, is displayed  -->     
    <em:name>My React test in Thunderbird</em:name>
    <!-- version number of addon -->
    <em:version>1.0</em:version>
    <!-- author's name -->
    <em:creator>david</em:creator>
    <em:targetApplication>
      <Description>
        <!-- Id to which mozilla application addon targets, curerntly Thunderbird -->
        <em:id>{3550f703-e582-4d05-9a08-453d09bdfdc6}</em:id>
        <!-- minimium version that the add-on supports -->
        <em:minVersion>35</em:minVersion>
        <!-- maximum version add-on supports, cannot be higher than current TB -->
        <em:maxVersion>49.0</em:maxVersion>
      </Description>
    </em:targetApplication>
   
  </Description>      
</RDF>