I would really really really like to see a message when you try to list an item
in a colour that it wasn’t ever known to be in a set. This would cut down on
the HUGE number of mislisted incorrect colours. It would be a huge help. And
those of us that are really listing rare non-production colours would probably
be fine with clicking the “yes, I know this is crazy rare, I want to list it
“ button. The known colours info is already on the site, but many BL sellers
are obviously not looking at it.