Several new IRCv3 features were added, particularly the improved IRCv3.2 capability negotiation, cap-notify, userhost-in-names, SASL reauthentication, and the MONITOR client notification system. Additional new channel features include WHOX support, KNOCKing, join throttle mode (+j), no forward-mode (+Q), and the long-planned MODESYNC mechanism, which helps maintain network-wide channel mode synchrony even when some modes are not enabled on all servers. The built-in DNS blacklist checker now supports IPv6 blacklists and has improved caching helping to decrease the effects of malicious attacks. Further work on TS6 and JELP includes improved ban propagation and more S2S security measures.