CommandBarComboBox.BuiltIn Property (Office)
Gets True if the specified command bar control is a built-in control of the container application. Returns False if it's a custom control, or if it's a built-in control whose OnAction property has been set. Read-only.
The use of CommandBars in some Microsoft Office applications has been superseded by the new ribbon component of the Microsoft Office Fluent user interface. For more information, search Help for the keyword "ribbon."
expression A variable that represents a CommandBarComboBox object.