Some widgets that appear as a single object on the Palette are actually Compound Objects that are made up of several Motif widgets. For example, the XmMessageBox is a compound object made up 6 child objects. You can toggle whether Compound Objects are expanded or not in the Browser by setting/unsetting the toggle "Show Compound Children" under the View menu of the Main Window. For example, if you did not want an "OK" button, a "Cancel" button, and a "Help" button, you could select "Show Compound Children" and then delete one or more buttons.