How can you tell that any Windows or Mac clone UI is a re-implementation? Easy: try to move your mouse diagonally into the Send To menu after letting it pop up. If the send-to menu closes as you mouse over the item into the submenu, it's a clone. If the menu stays up even if you brush over another menu item, it's either real or a Good Clone. :)
For the fun history, @DonHopkins had a thread a few years back:
For the fun history, @DonHopkins had a thread a few years back:
https://news.ycombinator.com/item?id=17404345