Color/Saturation
The dialog for adjusting the color/saturation can be started by clicking on "Colors -> Color/Saturation" in the user menu.
The Color/Saturation command is used to adjust the color and saturation of a single monochromatic channel or of an entire image.
When the option "Master" in the window "Color" is chosen, the process of adjusting affects all colors in an image. When a previously set color range is chosen, a manual marker and eyedropper become accessible.
A color range, which depends on the Color, Saturation, and Lightness values, can be narrowed or expanded.