In some levels with the Candy frog, you may enter into a situation that the only available move is the frog. But in some levels like 15263 you may enter into a situation that the frog is ready to be used no matches can't be done after two shuffles and you will lose the level instead of letting the game to allow you to use the frog and finish the level just like in the old Flash version.
So shuffling shouldn't be done if the only available move is the Candy Frog like in the old Flash version.
This also resulted in the loss of Super Charger and the high 700+ win streak