>>>>A lot of times the user won't be using the mouse but the keyboard to scroll through a combobox list, so click() won't fire.
>>>
>>>Use Programmatic/Interactive Change and don't worry about user navigation skills.
>>
>>This will not work since the user can simply tab over the field without changing anything. Since no change has occured, the interactive change will not fire.
>
>But what's the idea to check if no change happened?

Because the combobox value is initially blank. Once it has focus, the user should not be able to leave it blank.