How do you remove the White Space on a DropdownField Component

The only other option is to allow a placeholder initially, but null it out if the user makes a selection (blocking them from de-selecting it essentially), thus you could not utilize this for optional fields.

a!localVariables(
  local!options: {"a","b","c"},
  local!selected,
  
  a!dropdownField(
    label: "Dropdown",
    placeholder: if(rule!APN_isBlank(local!selected),"-- Select --",null),
    choiceLabels: local!options,
    choiceValues: local!options,
    value: local!selected,
    saveInto: local!selected
  )
)