ameter" id="ServiceExtensionHandler-param-parameters"><span class="type-annotation"><a href="dart-core/Map-class.html">Map</a><span class="signature">&lt;<wbr><span class="type-parameter"><a href="dart-core/String-class.html">String</a></span>, <span class="type-parameter"><a href="dart-core/String-class.html">String</a></span>&gt;</span></span> <span class="parameter-name">parameters</span></span>)
    </section>

    <section class="desc markdown">
      <p>A service protocol extension handler. Registered