Hover over folders, click on folders, or drag one of the folders into another folder. Hopefully it'll be nearly 1:1 with the behavior of real icons on a Windows 10 desktop... hopefully.
I'm not entirely sure why I made this. I originally made this four years ago here... https://scratch.mit.edu/projects/10082368/ ...and I was having a walk down nostalgia lane earlier today, looking through my old Scratch projects. I found this 'Desktop Dragging' project of mine and became unusually fixated on solving all of the problems with it. This version is the product of that experience, so I've completely re-done the whole thing from scratch (heh) in such a way that the number of folder icons sprites that can work is unlimited (providing you edit the 'touching folders' condition for when a folder is moved into another to account for all other icons). I also updated the look so it replicates Windows 10.