By default, PDF Vouchers support four recipient fields, as below :-
Recipient NameRecipient EmailRecipient MessageRecipient Gift DateYou can view them from Add/Edit Product page -> PDF Vouchers -> Gift Voucher as shown in below screenshot :-
Adding a new recipient field to pdf voucher is very simple, it is just two simple functions attached to WordPress hooks. The structure of the function looks as below :-
Adding this code in your child theme's function.php file or in custom add-on, will generate a new "Recipient From Name" section as reflected in below screenshot :-
text - Shows a text field, same as Recipient Nametextarea - Shows a textarea field, same as Recipient Messageemail - Shows a Email field, same as Recipient Emaildate - Shows a Date field, same as Recipient Gift Date