Currently the Lightweight rendering mode is currently supported by the RadCalendar, RadComboBox, RadDock, RadFormDecorator, RadMenu, RadToolTip and RadWindow controls. Section illustrating this rendering is available as demo
for each of these controls.
The RadGrid has this property as it is a RadCompositeDataBoundControl as is the RadComboBox. The property is defined in their base class because it will be gradually implemented for all such controls in the future.
I hope this information will be helpful to you.
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