Puzzle 3790 silly stockfish engine?

http://de.lichess.org/training/3790

Mate in 6. Winning move is Rf8+ and Re8+ to force the king to the side to mate. When started stockfish analysis board to check, it gave Rg2 with a draw (0) hahah. After i ve done Rf8+ move stockfish found mate in 7 due to its inacurate Rh5 move instead of Rh7. hahah. its funny that players get punished for inaccurate moves...

The local analysis is limited, it is running with javascript in the browser.

Looks lite this puzzle has 40 retry moves ;)