Eraser support for Magic Markers

The Magic Marker is a great upgrade from regular markers, supporting on-the-fly colour swapping & pressure sensitivity in VR. However, there is no way to enjoy these benefits with a standard Eraser marker.

This request is for the Magic Marker to support swapping to an "Eraser" colour, that allows users to erase portions of their art with pressure sensitivity, all without having to drop the marker.