iDad5

I'm actually lost right now in a problem of my own, but as yours seemed related I checked, and it seems to me at a cursory glance that 'defererInstance' should be an Array of ScrollTrigger instances.  So, you might have to execute update or refresh on the members, not on the array itself?

My bad, your walk never ends  So onRepeat is what you are looking for. 

I'm not at all familiar with Webflow, but as a  general hint, I would remind you that ScrollSmoother is an addition to ScrollTrigger and ScrollTrigger needs GSAP to run, so usually you at least need to 'paste' all three of those in your page's head, if that is the only way you can go.

See the Pen GRxMdoz?editors=1111 by mdrei (@mdrei) on CodePen
 
is that what you are looking for?
 
[Edit: I striped it down to the bare bones, and you would have to guard against dragging out, you could do this by setting drag boundaries, or checking inside the onDragEnd...]

You could try to start the video on mousedown (when the user starts dragging) and immediately pause it. After that you should be able to play it programmatically ever after

Thank you Jack for your answer. 
 
First of all I have to report that I made a CodePen (my first) and I got it to work the way I wanted and expected.
 
to 1: I thought exactly that way, but I found multiple answers that suggested that create() would be the same as the constructor and as both worked / not worked the same way for me I grew uncertain. And create was said to be the preferred method of creating a Draggble (?) The documentation is - at least for me - not to clear either.

to 2: I did (
See the Pen jOVqdWv by mdrei (@mdrei) on CodePen
) and it worked. I have to see if there is something I couldn't fin in hours of searching in  my code that was wrong, or if my setup (locally hosted gsap) is buggy in a strange way.

to 3: I resorted to Draggable.get('#id').y in the end, but just wanted to understand...   
THX again