When you have multiple chat/IM/messenger windows open with different people simultaneously and you inadvertently type and send an insulting/offensive/insensitive comment in the wrong chat window, specifically the one with the person referred to.
Mike

(4:45p) Dude, what's up?

Me_Gaxxy
(4:45p) Hang on, on another chat...

16:45 <Dave> Hey, how's it going?
16:46 <me_gaxxy> Ugh, freakin' stupid Dave trying to chat me...
16:46 <Dave> WTF???
16:47 <me> Whoops, chat faux pas..
by DanGarPrius August 15, 2013
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