#2811 unexpected colorbox with "with polygons fc variable" in development version

[Hiroki Motoyoshi]

In the development version, when using "with polygons fc variable", an unexpected colorbox is displayed by default.

This is a sample script.

$data <<EOD
0 0 1 1
1 0 1 1
1 1 2 1
0 1 2 1
EOD

set xrange [-1:2]
set yrange [-1:2]
set isotropic
set xyplane 0

splot $data using 1:2:3:4 with polygons fc variable

The output from the sample script is attached.