diff --git a/webrtc.html b/webrtc.html
index 348e94c52..9bb822275 100644
--- a/webrtc.html
+++ b/webrtc.html
@@ -17402,8 +17402,7 @@ <h2>
                 <li data-tests="RTCError.html">
                   <p>
                     Set all {{RTCError}} attributes of <var>e</var> to the
-                    value of the corresponding attribute in <var>init</var> if
-                    it is [=map/exists|present=], otherwise set it to <code>null</code>.
+                    value of the corresponding attribute in <var>init</var>.
                   </p>
                 </li>
                 <li class="no-test-needed">
@@ -17497,10 +17496,10 @@ <h3>
         <div>
           <pre class="idl">dictionary RTCErrorInit {
   required RTCErrorDetailType errorDetail;
-  long sdpLineNumber;
-  long sctpCauseCode;
-  unsigned long receivedAlert;
-  unsigned long sentAlert;
+  long? sdpLineNumber = null;
+  long? sctpCauseCode = null;
+  unsigned long? receivedAlert = null;
+  unsigned long? sentAlert = null;
 };</pre>
           <p data-dfn-for="RTCErrorInit">
             The <dfn data-idl="">errorDetail</dfn>, <dfn data-idl=