RGBfg=r, g, b {,index}
RGBfg has the same syntax and semantics as RGBbg except that it defines a foreground (text) color rather than a background color. The screen shot under RGBbg shows a custom foreground color for the first column.
Originally, row colors (see Cformat C and c) were drawn only from the A-Shell palette, and identified by the palette index numbers 0-15. You can define a custom color using RGBfg or RGBbg on the RGB Color Index and then use it for a row foreground color by specifying the RGB Color Index.