signal-spam.xml

<Root>
  <commands>
    <cmd name="SignalSpam" _label="Report SPAM"
      _tip="Report this as SPAM to Signal Spam"/>
  </commands>

  <menu>
    <placeholder name="MessagePlaceholder">
      <submenu name="Message">
    	  <menuitem name="SignalSpam" verb=""/>
      </submenu>
   </placeholder>
  </menu>
</Root>