Hey,
Sorry it still doesnt work for me, also I found another problem.
Here are screenshots of what is going on,
The child named "D" is lazy loaded:
After typing "D" in the filter all the data is gone:
Also,
Typing "B" in the filter, then opening and closing a few times the node "B" (No child is loaded because he has only
one child named "D" and the filter is "B") :
Then remove filter, and "D" is duplicated: