The page we used to use as the source (foundation.app/Username/Collection/ID) was changed (foundation.app/mint/eth/Contract/ID), and apparently accounts (29hyeon) can be deleted and some thumbnails still appear on the artist's and owner's galleries but they return 404 pages when you try to open them (see bad_foundation_id; according to their policies NFTs can be removed/set to private, but I'm not sure if it's the case here). The bookmarklet no longer works, but you can still access the images, including those that return 404 pages.
Updated