en passant
no option to turn en passant on/off. It is a rule of chess, just like castling Kingside and castling Queenside are moves.
No joking; this original poster may be asking a serious question here. To capture en passant simply move your pawn to the desired square (like any other move) and chess.com removes the captured pawn for you (like it always does).
Let's say White has a pawn on a5 and Black just just played b5 (from b7). Simply move your pawn to b6, and chess.com recognizes axb6 (e.p.) - which automatically removes the Black b5 pawn.
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