It’s actually a very simple application that has been open source developed and with which you can chat and connect to any IRC server without having to install the mIRC application on your system as the program is itself a complete client.
The program includes tones of advanced features with which to overshadow the now classic mIRC, such as a favorite channels list, automatic bans, direct access to the whois command, server lists, etc.
Plus, the whole look and feel of the program can be modified with the configuration options, with which you can determine the background colors, text colors, and other elements.
X-Chat is the IRC alternative you have been waiting for.
Trial version is functional for 30 days.