Raycaster no longer works

[Mugen87]

This is actually a duplicate of:

Issue with mouse events when updating from r119.1 to r120.1

This is because of a change in r120 which is highlighted in the migration guide: OrbitControls as well as other controls were moved to the Pointer Events API. In your case, you have to register your event listeners to pointerdown and pointerup events instead. The reason behind this is that OrbitControls calls preventDefault() on Pointer Events in certain cases which automatically cancels the respective mouse events.

It’s unrelated to Raycaster. The problem is that your mousedown event listener does not fire anymore. You have to use the pointerdown event.