Colors on [[Special:SupportedLanguages]]
Colors on Special:SupportedLanguages
Color codes shown with user names on Special:SupportedLanguages are grossly incorrect, off by dozens of months, even half-dozens of years.
Example: Tilla contributed the latest to Ripuarian in 2008 but is shown with a green underline in Special:SupportedLanguages/ksh.
Btw. it is not clear and should be mentioned whether colors meant for contributions to the particular language or contributions in general, but neither would be accurate.