Features that worked in mIRC in the 1990s are broken, like sending messages. Right this second if I click to reply to someone's message, I can't add a message in Japanese unless I copy-paste it in. This happens every few months. I can't tag people who have non-English names reliably.
It crashes my browser. There are weird security settings, and when you have multiple environments, it is completely unusable without having multiple browsers. Sometimes you can't log in without clearing your cache completely.
It is sheerly anti-organic, adding features no one wants.
I'm literally taking time out of my vacation to complain about it, fml.