Can I activate camera to go underground again?

In https://github.com/AnalyticalGraphicsInc/cesium/pull/8504 for Cesium v1.66 a “bug” was fixed, where the camera could go underground during mouse navigation.

As I use Cesium to display geological layers below the earth’s surface I have to go with the camera under the ground.

Is it possible to activate this functionality again?

The old behavior only allowed the camera to go underground while the terrain tiles were still loading. Was that a sufficient condition to always enable you to go underground in your app?

You can actually just disable terrain collision in the camera controller, so you can move freely underground:

https://cesium.com/docs/cesiumjs-ref-doc/ScreenSpaceCameraController.html?classFilter=ScreenS#enableCollisionDetection

viewer.scene.screenSpaceCameraController.enableCollisionDetection = false;

``

At some situations it was possible to move the camera underground, yes.
But the disabling of CollsionDetection works fine, thanks.