SyntaxError: Unexpected token N in JSON at position 0

[3ch01c]

This error message is displayed if a puzzle.json resource is no longer available. This happens if you reinstall a mothball with a different seed. To fix it, you need to hard reload the /puzzle-list.html page to get the new puzzle endpoints. The error message should point the user to this problem (e.g. display a 404 instead of trying to parse the nonexistent JSON)