I’ve had this problem a few times before, but tonight in a Mythic +10 I was tanking a big pull and my character just froze, stopped responding to commands. I realized after a few seconds that my rotation and footwork were getting dumped into a chat message instead, and tried to put a stop to it, but it took quite a lot of effort to get that chat box to quit! And then, it happened again a few seconds later. Fortunately, the healer had things in hand and we survived (the key upgraded +2).
Does anyone have a trick to disable chats during dungeons so that this won’t happen? I feel like it must happen because somehow my mouse pointer went down there and clicked. In PuGs, it’s important to say some things now and then, so it would be good if I had a keyboard-only method to start the chat, but it’s very tricky for me to devise a way to have chat functionality without it accidentally absorbing my rotation and defensives.