Drag preview icon should display under cursor (or at least close to it)

[Skaiir]

Describe the Bug

Currently, the drag preview does not appear under the cursor, but displays offset relative to where it was grabbed from, which makes it a little clunky to drag around (it becomes uncertain whether to use the mouse or the preview as the drop target).

Where the preview appears when grabbed at the rightmost point (red star)

Steps to Reproduce

1. add any field
2. start dragging it from its rightmost point
3. preview isn't under cursor, and remains offset until drop

Expected Behavior

3. preview should remain under the mouse cursor

[Skaiir]

Seems there some discussion around this topic:

• Custom offset handler bevacqua/dragula#285
• Dragged Element Wrong Position bevacqua/dragula#144

I think they key thing here is that the offset isn't configurable (yet). Something we could bring into our own dragula fork, and the dragula 2 in the future.

[pinussilvestrus]

The maintainer of dragula@2 is currently working on exactly that: #588 (comment) 🎉

[Skaiir]

Closed via #1267