Check invitee supports MIX

xep-0369.xml

@@ -44,6 +44,7 @@
       Editorial Updates;
       Clarify Access to MAM history, prior to user joining channel;
       Add option for user to join without presence;
+      Check invitee supports MIX;
     </p></remark>
   </revision>
   <revision>
@@ -1547,6 +1548,7 @@ This approach  enables flexible support of multiple clients for a MIX channel pa
 
       </p>
       <ol>
+        <li>The inviter checks with disco that the invitee supports MIX.</li>
         <li>The channel inviter sends to the channel requesting an invite for the invitee.</li>
         <li>The channel sends an invitation to the inviter.</li>
         <li>The inviter sends the invitation to the invitee.</li>