Hi Stian Valsvik,
The behaviour that you describe is by design and is correct.
When an item is selected and dropdown opens - the selected item should be displayed on top of the dropdown.
Please take a look at this online demo
where you will be able to test how RadComboBox works under different configurations.
For example if you increase the Width and DropDownWidth of the RadComboBox on the demo (for example to 300px) - the control there will behave exactly the same as the RadComboBox that you have implemented.
the Telerik team
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