incorrct "game over" in Crazyhouse

This screenshot: ibb.co/d8x7GT shows a position in a Crazyhouse game that would be checkmate in standard chess but isn't in Crazyhouse; nevertheless, the display says "Spiel vorbei" ("game over") and doesn't load the engine.

Here's the game: lichess.org/XFBMd4C6

How is this not checkmate?

It is a checkmate in crazyhouse.

If that's a checkmate, do explain how R@g8 is not a legal move for black?

@GBA87 & @lovlas
The issue is not with the game, but rather with the engine; in the screenshot, the engine says the game is over immediately after 32. Qxf8+. Nothing serious here, just an issue with the engine.

The engine works fine for me. Weird. What browser are you using?

Hmm, might just be a bug, Try refreshing it.

@lovlas
I'm using Chrome, personally. It shows the evaluation for me as mate in one, but it says "Game over." underneath where it usually says the number of nodes. In Firefox, I'm able to replicate the issue. I can't speak for the OP though.

@lovlas, as for me, Chrome, and I have the engine crashing for me all the time. I won't even make a forum post when it happens, because it's so often. I don't play crazyhouse, but weird stuff happens in any kind of evaluation, like null moves (e.g. 21.--) especially when the engine is mistaken about whose turn it is.

I'm saying this because you said it's weird, but I thought it was something usual that you would already be addressing quite often.

I confirm the issue both in Firefox 60 and Chromium 66. On the 32th move the engine says "Game over" instead of suggesting the moves like N@g8 and R@g8. Hard refresh doesn't help.