In response to disco#items, the server returns a list of services, for each of which we request disco#info. E.g. on jabber.at this gives <item xmlns="http://jabber.org/protocol/disco#items" jid="conference.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="echo.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="icq.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="irc.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="proxy.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="pubsub.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="upload.jabber.at"/> <item xmlns="http://jabber.org/protocol/disco#items" jid="webpresence.jabber.at"/> The problem is that the current code assumes that if the response for one of these contains a feature of namespace http://jabber.org/protocol/muc, that that service is the MUC room service. That assumption is wrong. For example, the IRC transport has <query xmlns="http://jabber.org/protocol/disco#info"> <identity xmlns="http://jabber.org/protocol/disco#info" category="conference" type="irc" name="IRC Transport"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="http://jabber.org/protocol/disco#info"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="http://jabber.org/protocol/muc"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="jabber:iq:register"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="vcard-temp"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="http://jabber.org/protocol/commands"/> <x xmlns="jabber:x:data" type="result"> <field xmlns="jabber:x:data" var="FORM_TYPE" type="hidden"> <value xmlns="jabber:x:data"> http://jabber.org/network/serverinfo </value> </field> </x> </query> or the ICQ gateway <query xmlns="http://jabber.org/protocol/disco#info"> <identity xmlns="http://jabber.org/protocol/disco#info" category="gateway" name="ICQ Transport" type="icq"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="jabber:iq:register"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="jabber:iq:gateway"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="jabber:iq:private"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="http://jabber.org/protocol/disco#info"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="http://jabber.org/protocol/commands"/> <feature xmlns="http://jabber.org/protocol/disco#info" var="http://jabber.org/protocol/muc"/> </query> The current code will use the last incoming disco#info response with a http://jabber.org/protocol/muc namespace to set _mucService. And so it will usually get it wrong.

Comment on attachment 8779332 [details] [diff] [review] v1 - set _mucService according to namespace, category and type Review of attachment 8779332 [details] [diff] [review]: ----------------------------------------------------------------- ::: chat/protocols/xmpp/xmpp.jsm @@ +1825,5 @@ > } > let features = query.getElements(["feature"]) > .map(elt => elt.attributes["var"]); > + let identity = query.getElement(["identity"]); > + if (identity.attributes["category"] == "conference" && if (identity && ... The node may not exist.

Comment on attachment 8779336 [details] [diff] [review] v2 - set _mucService according to namespace, category and type Review of attachment 8779336 [details] [diff] [review]: ----------------------------------------------------------------- Who knows, maybe this will turn out to help clokep's strange gmail bug...