Comment 3 for bug 170194

I think this feature for allowing users to define their own
named colours could probably include all the 'standard'
named colours as defaults.

A possible inelegant hack/workaround would be to create
single colour gradients made using named colours and have
them listed in the gradients dialog but I'd really prefer to
see an enhancement to the GTK colour picker first, that
allowed you not just to input named colours but to choose
from a list of all the available named colours.