Click on the
Show cells option in the
Edit menu to toggle the display of cells "on" or "off". When toggled "on" a green indicator is visible and the cells are displayed in the viewer window (as shown below).
NOTE:- The active property displayed in the cells is set via the Cell Properties menu, which and how the cells are displayed is determined by the Cell Controls settings and the colour display is determined by the Colourmap Editor settings for Cell colours. 
