Use Room Title
Problem
The window title of group chats is currently the part before @ in MUC JID, and the heading in the banner is the JID. The pre-@ part is also used for bookmarks.
Analysis
This is often not very descriptive? And since XMPP-MUC has a "Room Title" field, why not use it?
Enhancement recommendation
Send this:
\<iq to="room@conference.example.org" type="get">
\<query xmlns="http://jabber.org/protocol/disco#info" />
\</iq>
Then use iq/query/identity/@name
as heading, window title, default bookmark name etc.