In Customize Ribbon window, I double click one item in the left list, the selected item will be added into right list, it is strange that the selected item after double clicking is not the double clicked one, it is the item under the double clicked one.
For example:
item1 | item1
item2 ---> double click it | item2
item3 | item3 ---> this one is highlighted
I think it is a defect. I am using 14.1.0.41.