Minimal reproduction of the bug/regression with instructions:

Updating nodes and calling treeModel.update() with virtual scroll leads to a collapsing tree and finally a tree stuck in loading... This is only present in virtual scroll. Setting virtual scroll to false will fix the problem.

Stackblitz uses an example where the child nodes are loaded in steps with a load more functionality 100 nodes each time.

Link to Stackblitz reproduction

Repo steps:

• Open root node
• Click load more
• Root node will collapse
• If this is repeated multiple times tree is stuck in loading...

Expected behavior:

Tree behaves the same in virtual and non-virtual scroll.

Versions of Angular Tree Component, Angular, Node, affected browser(s) and operating system(s):

First noticed in version 8.5, still there in 10.0.0.

Other information: