Mozilla is giving up on their IRC server

Suffice to say that as a globally distributed organization, Mozilla has relied on IRC as our main synchronous communications tool since the beginning. While we still use it heavily, IRC is an ongoing source of abuse and harassment for many of our colleagues and getting connected to this now-obscure forum is an unnecessary technical barrier for anyone finding their way to Mozilla via the web. In the next small number of months, Mozilla intends to deprecate IRC as our primary synchronous-text communications platform, stand up a replacement and decommission irc.mozilla.org soon afterwards.

Source: exple.tive.org