### Godot version

v4.0 rc6

### System information

Windows 10

### Issue description

When using a ViewportTexture from a SubViewport on a TextureRect, it throws errors after running the scene once and then switching scenes in the editor.
![Pasted image 20230227212626](https://user-images.githubusercontent.com/44676282/221680047-984fa03e-33d1-4856-9a7f-1700b28423cf.png)


### Steps to reproduce

Run the canvas-scene once.
Switch to another scene in the editor.
Switch back to the canvas-scene

### Minimal reproduction project

[ViewportTextureError.zip](https://github.com/godotengine/godot/files/10844099/ViewportTextureError.zip)

} else {
				last_id = physics_object_capture;
				last_object = capture_object;
			}
		}
		if (pos == last_pos) {
			if (last_id.is_valid()) {
				if (ObjectDB::get_instance(last_id) && last_object) {
					
					_collision_object_3d_input_event(last_object, camera_3d, ev, result.position, result.normal, result.shape);
					if (last_object->get_capture_input_on_drag() && mb.is_valid() && mb->get_button_index() == MouseButton::LEFT && mb->is_pressed()) {
						physics_object_capture = last_id;
					}
				}
			}
		} else {
			if (camera_3d) {
				Vector3 from = camera_3d->project_ray_origin(pos);
				Vector3 dir = camera_3d->project_ray_normal(pos);
				real_t far = camera_3d->far;
				PhysicsDirectSpaceState3D *space = PhysicsServer3D::get_singleton()->space_get_direct_state(find_world_3d()->get_space());
				if (space) {
					PhysicsDirectSpaceState3D::RayParameters ray_params;
					ray_params.from = from;
					ray_params.to = from + dir * far;
					ray_params.collide_with_areas = true;
					ray_params.pick_ray = true;
					bool col = space->intersect_ray(ray_params, result);
					ObjectID new_collider;
					CollisionObject3D *co = col ? Object::cast_to<CollisionObject3D>(result.collider) : nullptr;