Colors of clippings in 3d scatter plots do not match original colors

[nvaytet]

Example:

import plopp as pp
import scipp as sc

a = pp.data.scatter(1000)
b = a.copy()
b.coords['x'] += sc.scalar(60, unit='m')
pp.scatter3d({'a': a, 'b': b})

And then make a spatial clip in Y using the clip3d tool under the figure, the green and red opaque clipping should be blue and orange instead, respectively.

This is because the clippings are added as new data on the figure, and they automatically get given an incremented artist number, which cycles through the colors.

We don't see this when using cbar=True because all artists are using the same colormapper.