[cmoski]

Notifying you about messages you've already seen. You have to change chats and to back for it to dismiss it. Kills me.

Likes to open new windows if you click a notification.

It is slow.

The search is not good at showing multiple results from the one chat. Why does it search all the other chats anyway...

Switching accounts constantly is a pain in the arse - I unfortunately have to use four accounts and one sub-account (member of some other org's team or something).