Drop bar separator is left in place after releasing mouse on demo website

[julianpoy]

Describe the bug
After dragging a couple of times something causes the drop bar to get "stuck" unless I drag and drop again. This occurs on the demo website.

To Reproduce
Play around on the https://headless-tree.lukasbach.com/ website demo and it happens.

Expected behavior
The drop bar to not stay visible after a drop.

Screenshots

Additional context
On demo website. Tried using both Chrome and Firefox, happens on both.

[lukasbach]

Thanks for the report! The issue should be fixed now.