Horde with Antichess evaluation

To reproduce the bug:

1. Clone the study shown below.
2. Go to your clone via a link to the first chapter.
3. Navigate to the second chapter.
4. Promote the pawn. Notice that you can't promote to king; you are playing Horde.

Because you are playing Horde with Antichess evaluation:
a. The computer says "Blunder: Best was c8=K"; promoting to king is the only drawing move in Antichess.
b. The computer fails to make a move, as the best move in Antichess would endanger the king.

hi　　　　　　　　　　　

Nice bug report :) - i have tested it, did not fuzz around with the types of studies but the thing that struck me is that first chapter' position is impossible to reach in antichess :) - in the loosing all world there is always at least one survivor.
Its a special case, though it should be tested for different cases and for sure its possible to have a study with only a board.

Posting this comment in a thread that in antichess study you cannot promote to a King i have found that in puzzles you cannot promote your pawn to a rook - LOL - white give Checkmate with one move - and pawn gave mate attacking the whole 8th rank - imgur.com/a/YdGW4F3 :)

edit:
1. I dont know how can i modify the FEN of the first chapter in my own clone. Cant do it, cannot add a piece.
2. I have tested: remove first chapter, clone and then horde chapter suggests promoting to a queen which against a lone king is also a draw in horde, thats ok.
3. Deleting the first chapter without cloning afterwards leads to the same issue, but it is enough to refresh the page - my conclusion: a fault of the running Stockfish instance.