Originally posted by zucchiniThis might be a problem because FEN notation is universal. If you add new terms, it become a unique siglum style for this site.
1) An option to specify the board's orientation (white at bottom or black at bottom).
Originally posted by RolandYoungGot it. I guess I didn't know enough about webpage design to have commented
It's not necessary to extend the FEN notation to provide the feature Zucchini is asking for. It could be part of the tag: something like [fen]6r1/2R5/kp6/3bBpNP/p2P1P2/2P5/1P4P1/6K1 b - - 0 39[/fen] for white's view of the board
and [fen inverted]6r1/2R5/kp6/3bBpNP/p2P1P2/2P5/1P4P1/6K1 b - - 0 39[/fen] for Black's.