I noticed that some ui controls are not so reactive, this is more true with the tree widget.
Example :
I took dhtmlx demo dhtmlx.com/docs/products/dht … mance.html
and then this other one : wwwendt.de/tech/dynatree/doc/samples.html
If you respectivily play with the 1000 elements node, you have quite a performance difference. I don’t suggest to reach the performance of the last one but i think some significative speed improvements could be researched.