Additional value displayed when using default Static List field

When using the default Static List values and configuration, when adding a new entry or when editing the application, there are 4 values displayed, one of them being empty.

This is not the case if "Multiple Select" is selected (in that case the empty value does not appear in 'add' and 'edit' states).

Also because "Multiple Select" is disabled I would have expected not to be able to select multiple values from the list, see addingEntry-SelectingAll.png