[Gimp-user] Change columns in colormap dialog?

[plums <forums gimpusers com>]

Hi, in the gimp help for the colormap dialog, there is an image of a colormap of
6 colors, each fairly large squares in a 3x2 grid:
http://docs.gimp.org/en/gimp-indexed-palette-dialog.html

However I cannot find a way to change the colormap to have anything but 16
columns. As such, the only way to increase the size of the squares is to widen
the dialog, something I don't want to do.

Is there a way to change the column numbers, or otherwise enlarge the colormap
colours? If it had the same functionality as the palette editor dialog, that
would be perfect.

Using GIMP 2.8.10 on Win32.

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