Here’s a simple tutorial I’d like to share about customizing Chatzilla. By its official definition, Chatzilla is
A clean, easy to use and highly extensible Internet Relay Chat (IRC) client, built on the Mozilla platform…
This is one of my favorite add-ons to date. I use it mainly to communicate with other Mozillians around the world through different channels in moznet including #webmaker, #mozillians, #remo and the official cyber-tambayan of the Mozilla Philippines local community, #mozilla-ph.
By default, Chatzilla opens on another window. It looks good and neat.
But what if you would like to have it on the same browser window together with other tabs? How would you do that?
Simple. Just copy and paste this text to the awesome bar (the address bar) to open Chatzilla on a new tab:
See! You can then put Chatzilla permanently on your browser by pinning it as an app. Easy, right? You now have one less window to switch to.
Source : http://www.jeanaustinr.com/blog/how-to-put-chatzilla-on-a-firefox-tab-instead-on-another-window/