After migration from v1.7 to v1.8.4 moving items with display:none has strange behavior

[DenitsaGencheva]

Problem:

We use sortable extensively in our project for moving card components into different sections.
In one of the sections, the behavior is more of a dragover and drop inside the hovered element. That is why the ghost class is styled with 'display:none'. Dragging on top of the different elements (projects) was working without issue in v1.7. Now the card is added to the list, but sometimes it gets stuck at the bottom. Usually, this happens when I drag from bottom to top on the projects list.
We managed to improve the behavior by changing the style for the ghost class to:

width: 10px; height: 10px; margin-bottom: -10px;

I guess this is due to adding the new properties described here: https://github.com/SortableJS/Sortable/wiki/Swap-Thresholds-and-Direction#swap-threshold
but i can't figure out how to make it work with tweaking them.

Thank you in advance for looking into this!

JSBin/JSFiddle demonstrating the problem:

https://jsbin.com/qahuxaz/edit

[owen-m1]

@DenitsaGencheva Should be solved in commit above.