Do New Chat Rooms change anything about IRC?

There seem to be some minor differences. When I send a message to a room the server returns my own messages as PRIVMSGs as well on the same connection unlike normal chats where it doesn’t.
And justinfan doesn’t work for rooms apparently? FeelsBadMan

Anyone know if that’s intentionally different with rooms or maybe just bugs? I’m assuming intentional but thought I’d ask.