Hi Abhisek,
Volume models don’t have this color well in Model Panel.  The atomic models do.  It has always been this way, as far as I know.  See for example attached image with both kinds of models.

You can see/use color wells for the volume displays in the Volume Viewer tool.
I hope this helps,
Elaine
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Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco




On Feb 14, 2020, at 11:37 PM, abhisek Mondal <abhisek.mndl@gmail.com> wrote:

Hi,
Newest version of chimera does not have the color option in the model panel. Is this a bug of some sort?
Please see the attached image.
Regards
Abhisek