diff --git a/index.html b/index.html
index a8ed6e8..9f5042f 100644
--- a/index.html
+++ b/index.html
@@ -159,14 +159,32 @@ <h3>
       </p>
       <ol>
         <li>
-          <p>Set {{RTCRtpTransceiver/[[HeaderExtensionsToNegotiate]]}} to the
+          <p>If transceivers of the same kind exist in the current PeerConnection,
+            copy {{RTCRtpTransceiver/[[HeaderExtensionsToNegotiate]]}} from
+            the first such transceiver, in the order defined by the [=CollectTransceivers=] algorithm.
+            This ensures consistency across transceivers if they are added
+            after initial negotiation.
+          </p>
+          <p>If no such transceiver exists, set {{RTCRtpTransceiver/[[HeaderExtensionsToNegotiate]]}} to the
           platform-specific list of implemented RTP header extensions. The
           {{RTCRtpHeaderExtensionCapability/direction}} attribute for all
           extensions that are mandatory to use MUST be initialized to an
           appropriate value other than {{RTCRtpTransceiverDirection/"stopped"}}.
           The {{RTCRtpHeaderExtensionCapability/direction}} attribute for
           extensions that will not be offered by default in an initial offer MUST
-          be initialized to {{RTCRtpTransceiverDirection/"stopped"}}.</p>
+            be initialized to {{RTCRtpTransceiverDirection/"stopped"}}.</p>
+          <p>
+            If there are header extensions whose state needs to be consistent across all transceivers
+            in a bundle,
+            and any other transceiver exists that will be included in the same bundle,
+            copy the {{RTCRtpHeaderExtensionCapability/direction}} attribute
+            for that extension from that other transceiver.
+          </p>
+          <p class="note">An example of header extensions that need to be identical across all
+            media sections is the key management extensions from [[RFC4567]], as described in section 5.35 of
+            [[RFC8859]], where they have category IDENTICAL. If this is supported and negotiated as "sendrecv",
+            and a new transceiver is added, that transceiver needs to also have the extension as "sendrecv". 
+          </p>
           <p class="note">The list of header extensions that MUST/SHOULD be
           supported is listed in [[RTCWEB-RTP]], section 5.2. The "mid" extension
           is mandatory to use when BUNDLE is in use, per [[BUNDLE]] section
@@ -230,6 +248,14 @@ <h2>Modifications to existing procedures</h2>
               <var>transceiver</var>.{{RTCRtpTransceiver/[[NegotiatedHeaderExtensions]]}}
               to <var>negotiatedExtensions</var>.</p>
             </li>
+            <li>
+              <p>
+                Set <var>transceiver</var>.{{RTCRtpTransceiver/[[HeaderExtensionsToNegotiate]]}}
+                to <var>negotiatedExtensions</var>.
+                This ensures that unless further calls to {{RTCRtpTransceiver/setHeaderExtensionsToNegotiate}} are done,
+                subsequent offer/answer will not alter the list of extensions.
+              </p>
+            </li>
           </ol>
         </li>
       </ul>