3D representation disappear after apply color/opacity to slices

[bourdaisj]

Reproduction:

• Go to https://kitware.github.io/glance/app/
• Load the COVID-19 dataset from the sample data
• hit "apply color to slices" or "apply opacity to slices"

then the 3d volume is hidden

[floryst]

Not yet sure what the cause is. It might be a consequence of the volume and slice rendering sharing the same lookup table given the array name....