When clicking on "Model / Clear All", I think you need to reset the new model root (factory.setRoot(new Container()).
Otherwise this issue appears when executing a KevScript after a clear:
Uncaught Error: Add Trace source not found for path : / pending null
{"t":"a","s":"/","r":"nodes","p":"/nodes[node0]","n":"org.kevoree.ContainerNode"}
When clicking on "Model / Clear All", I think you need to reset the new model root (factory.setRoot(new Container()). Otherwise this issue appears when executing a KevScript after a clear: