While we wait for key rebinding (if we can then even rebind this, someone from KR let me know? ;x; )…
Who ever thought it was a good idea to make Alt-Tab the hotkey for switching chat tabs? It’s incredibly frustrating when I just want to alt-tab out of the game. System message being spammed with “You are not in a party” is pretty silly 
It wants to make you feel bad for not playing with friends
They fixed it in other version.
But it’s bugged again in international version.
You can rebind the keys directly in the game files if you are having a bad really time because of that.
I believe KR got an update last week to be able to change them in-game like it is meant to be in any game.