Mate in 4 against Stockfish level 6?

Some time ago my friend told me he mated Stockfish level 6 in 4 moves, I didn't believe him. Now he did it again (after trying a few times) and sent me a screenshot. What's going on here?!

Screenshot:

ibb.co/QHtnqKx

I don't even care.

Look a computer will do what it us programmed to do.

I would assume stockfish programmers are not this stupid. But I don't even care if they aren't.

But yes I would assume it.

How come it never plays like that against me? I can beat level 5 most of the time but don't think I've ever won against level 6.

If it allowed something like that, it hardly counts as a real win.

Stockfish Level 6 isn't always that good, you know. It blundered 2 rooks and a few pawns to me when I played against it with my other account, and I won effortlessly.

I won every game with Stockfish Level 8 (Three-check variant)
@corsara1

why doesn't your friend just show us the game link, instead sending that caveman style photo-of-the-monitor screenshot??

ps. a side-quest for those curious: try finding that particular game with the "advanced search" in lichess database yourself :D

@FrozenFractals2
Found this game from about 18 hours ago, about the last time this post was edited
From the screenshot, there aren’t a lot of useful things, but the position matches, and if you look there is an e in the top left corner which matches the “correspondence”

very nice detective work! @J_SEDA_conant good job!