Set username/hostname on users on JOIN regardless of whether we know theirs

already

modules/line_handler/channel.py

@@ -78,7 +78,6 @@ def join(events, event):
         events.on("received.join").call(channel=channel, user=user,
             server=event["server"], account=account, realname=realname)
 
-    if not user.username and not user.hostname:
     user.username = event["prefix"].username
     user.hostname = event["prefix"].hostname