Suggestions for Improving Esperanto Color Skill Tips and Notes Section
If you look at the tips for the color skill you'll notice there are no references to actual color names. This seems odd. I would expect a chart of common color names would be included in the Tips and Notes for that skill.
Something like this would work:
This is a quick list of common colors. I made sure it included all of the colors of a Newton disc.
It would also be nice to have a short blurb about how best to esperantize unusual colors in casual conversation. I'm sure this comes up at least occasionally and, at a glance, both Being Colloquial in Esperanto and Plena Manlibro de Esperanta Gramatiko appear to be silent on the matter.
It's possible that they (the course makers) considered such a chart unnecessary, as most of these words would be known or at least familiar from other languages for the average speaker of a European language.
It's also possible that they though that it would never really be utilized. I know that I, for one, don't really like lists and especially not memorizing them. This is one big reason why I like Duolingo.
Then again, it's entirely possible that they just didn't think about it, in which case they definitely should.