I use SkyCoord as a mixin quite a bit in tables - it's very common to have catalogs with RA/Dec coordinates as one of the axes, and of course it's convenient to just drop SkyCoord's directly into that.

However, if I try to vstack two tables with SkyCoords as one of the columns, I get the dreaded:

NotImplementedError: vstack unavailable for mixin column type(s): SkyCoord

This seems like it should be straightforward given that SkyCoords pretty much behave like table columns... Of course I'm sure it's not that simple... but it's a pretty important use case, and maybe it's time has come?

cc @taldcroft @mhvk

(this might be a duplicate of a more generic "make mixins of all types work"... but I didn't find an obvious one)