We started toreplace our controls by telerik ones and noticed that the combobox wasn't getting the background of the theme we are using (Office 2016). It was keeping a gray gradient background.
After some investigation with the XAML forTelerik.Windows.Control.Input, the style for NonEditableComboBox consists of a grid with two borders and a RadToggleButton inside of it.
After some investigation, I noticed that adding the following lines to the toggle fixed my problem:
(Height had to be added for the highlight border as well)
Is this a bug? Or the expected behavior is that when using a RadComboBox the developer wont be able to get the background from the theme or be able to set the height?