blurOnEmptyReturn-option

Currently when user presses enter key if there is active selection on drop down that option is selected. And some option is always active if there are any unselected options.

Sometimes that is not preferred action, e.g. when we have single-select input where empty value is valid input. Currently, user will clear input by pressing backspace and then tries to exit the field by pressing return. But instead of leaving input empty some option will be selected.

With this option no option will be selected if input is empty and user presses enter.