Workspace switcher - can I turn off display of program icon?

[Chris Green]

I use Workspace Switcher and have a couple of workspaces with two
large terminal windows that just about fill the workspace.  With the
default terminal icon shown in the Workspace Switcher it's very
difficult to tell which is the current workspace because there's no
background shown.

If I make the terminal windows smaller then the terminals are shown
blank in workspace switcher and it's easy to tell which is the current
workspace.

Is there any way I can turn off display of program icons in the
Workspace Switcher?

-- 
Chris Green