I was using Chrome with zoom at 100%
on puzzle
after solving, the Mission accomplished box successfully appeared, but the content was too large to be viewed all at once. A scroll bar was present, but seemed frozen and unavailable. When I decreased the zoom two steps, to 80%, the scroll bar was then usable and one could scroll downwards to see the bottom of the content. Restoring the zoom to 100% seemed to freeze the scroll bar again.
