If you are using Dual display and you select a folder and then click on Duplicate inside the copy dropdown window, unless you have both windows pointing to the same location the Duplicate copy will not take place with the rename operation, just a copy to the location that the other window is pointing to.
Is this how the operation is supposed to work? Both windows have to show the same location?
Check that the menu item runs
Copy DUPLICATE in your toolbars in case it has been changed from the defaults.
It seems to work correctly here: