Hi! Clone is not supported yet, but you can use Serialize() and then Parse() to clone a control. However, it will not clone observables, since they are not serializable. (Only things that can be serialized into a JSON object.)
I would recommend just having one ADT, and creating a “template” container inside of that which you can serialize and then make invisible. Then, you can just Parse() it to clone it for as many items in your user list as you need.
Here’s an example of doing just that: How to add unknown number of Items to a StackPanel made in the GUI editor? - Questions - Babylon.js (babylonjs.com)