add mistakes button to puzzles
today in a rated puzzle I could not find a solution for a long time, it turned out that the puzzle had a mistake, and it would be convenient to make the omission button.
there are many suggested solutions, but I think that the moment when the white rook is given to the king is unacceptable at this level
yes Qxf2 is the best move, then white moves Rb8, then black Kh7, and here the best move for white is Kh2, black takes the knight and the puzzle can be finished. White can get away from checkmate without giving up the rook.