The list of available options (icons) in the popup-menu may be configured by the developer. For example, a final user does not, in fact, necessarily need to have access to CSS debugger.
The icons are default named in the order : 'a', 'b', 'c', 'd', ...
When Popup widget, Workstation widget or Genesis widget is created, simply position the resource XmNactiveIcon .
Example : In order to access 'a', 'c', 'e' and 'd' icons only :
...
XtSetArg(args[n], XmNactiveIcon,"aced"); n++;
...