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Additional item options

label_persons (label for multiple person reservation)
This option setting for a reservation accept multiple persons. Set item name(label) to input how many.

For example setting as "label_persons=Persons". In additional item like as "Persons,select,1,2,3,4" that make to recommand numeric choice field.

And example use "Additional Items" for event admin form.
Name*,size=40
Address,
Persons,select,1,2,3,4,5
Reservation person can choose reservation members count.