Weird only when you are not aware of the hidden information regarding the proximity of the 50-move line which is registered in the FEN - which you can view in the Analysis module. If black puts one foot wrong, it's a draw!
In a serious composition environment this counts as cheating but chess.com has an affinity for the game player scenarios where weak opponents may waste over 40 moves before they come near a checkmate finish. And then suddenly they need precise play to reach the target!
Chess Puzzles - Learn Themes and Patterns - Chess.com
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