I have two applications which both manage hierarchies using treeviews, allowing dragging and dropping of items into a hierarchy tree.
Sample1.jpg shows the working application, whilst Sample2.jpg shows the problem one.
They both work, but on one, the treeview correctly displays the lines to indicate where an item will be dropped, whilst in the other, the line is not shown apart from a tiny dot. I've compared the two applications, and switched out the bootstrap themes and styles, and cannot identify the issue. In the DOM explorer, the treeview styles look the same.
The malfunctioning application is using version 2019.1.220 of the framework.
Any help to fix this issue would be appreciated.