If you expand a tree node with 1000 items in it, and that tree has an ng-template the performance is very poor. It takes 7 seconds on my machine, see here https://www.telerik.com/forums/slow-treeview-with-large-datasets

Please add virtualisation to the TreeView so that not so many DOM elements (and therefore ng-templates) need to be created.

When using the "checkBy" attribute to configure the data field for the key definition, then the indeterminate state of parent nodes is broken.

To reproduce the issue have a look to this StackBlitz: https://stackblitz.com/edit/angular-okpokx

The functionality we would love to see is the ctrl+click/shift+click functionality for selecting checkboxes more efficiently. The reason for this is in several use cases, our users will have 100+ items to select under a single parent. In many cases, they will need to select about 1/2 of them. So the only option at that point will be to select all 50 or select the entire parent and 50.

Having a mechanism to more efficiently select/ (such as shift+click) would be ideal.