Indeed the have improved the Tabbing behavior of the control since the Q3 2013 version. Now it behaves the same way as the native WPF ComboBox. The Tab key navigates through the items instead of going to the next control. However what I can suggest you as workaround would be to manually Focus the next UI element by hooking to the KeyDown event of the Grid inside of the drop down portion of the control. You can get that Grid in the DropDownOpened event handler and hook to the KeyDown as shown below:
sender, EventArgs e)
var grid = (sender
And implement the following KeyDown handler:
sender, KeyEventArgs e)
(e.Key == Key.Tab)
var selectedIndex =
.Combo.SelectedIndex = selectedIndex - 1;
Note that you would also need to cover all the border cases here (for example when click tab on the last item).
Hope this helps.
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