in the case of intances , What is the reason why the mesh has always been selected
box.alwaysSelectAsActiveMesh = true;
instance.alwaysSelectAsActiveMesh = true;
This ensures that all 10,000 instances are always displayed.
Because of scene.freezeActiveMeshes();, the system will only draw instances that are visible at the time of the call, even if you move the camera. By setting alwaysSelectAsActiveMesh = true, all instances are visible from the start.
thank you