I know how to snap and make a modulo on a draggable element, but for no-touch device, a "fake scroll" looks a better idea.
How to make it (draggable update ?) ?
See the Pen aamypq?editors=0111 by benoitwimart (@benoitwimart) on CodePen
As I understand it this could be a bit tricky or messy.
The key to getting the scrollY of the window to effect the movement of the box is to use ThrowPropsPlugin.track() method to track the velocity of the scrolling.
When the user is done scrolling you can create a tween of the box based on the velocity of the scrolling.
Definitely study the ThrowPropsPlugin docs: https://greensock.com/docs/Plugins/ThrowPropsPlugin
and the track() method: https://greensock.com/