I agree with diane that Javafibs is best, but on the other hand, a chat box popping up in front of you can keep you from perhaps not seeing an important chat (which has happened to my while acting as a Tournament Director).
For other reasons, I do not use 3Dfibs for directing tournaments.
What I found helpful while using 3Dfibs was to move the box over so that it does not block your board when it pops up, thereby allowing you to see, but ignore, if you want, the chat box that pops up again and again.
Until you spread your wings, you'll have no idea how far you can walk. - Lithograph from Despair.com