The <code>priority</code> attribute returns the priority for
      this <code class="idl"><a data-link-type="idl" href="https://w3c.github.io/webrtc-pc/#dom-rtcdatachannel" id="ref-for-dom-rtcdatachannel①">RTCDataChannel</a></code>. The priority is assigned
      by the user agent at channel creation time. On getting, the
      attribute MUST return the value of the
      [[DataChannelPriority]] slot.</p>
   </dl>
   <h3 class="heading settled" data-level="4.2" id="new-rtcdatachannelinit-member"><span cla