Chat built into the browser was actually considered when i created it. I thought of a few ways to do it, one was to have a server say if it had an IRC channel then connect to that from within the browser. Another way was to have a fully functioning chat client complete with rooms for each server but also global chat to talk to anybody else running the browser.
In the end the idea was scrapped due to it not being required and would probably just end up being spammed. No point spending a lot of time implementing something that will be abused and rarely used for its intended purpose.