invoice_additional_settingThe invoice additional setting.field_nameenum<invoice_additional_settings_field>OptionalThe field names for additional sections in the invoice.Allowed values"ATTACHMENT"The file attachments added to the invoice."MEMO"The internal memo in the invoice that is visible only to the invoicer."REFERENCE"The reference number in the invoice for tracking or correlation.display_preferenceobject<display_preference>OptionalThe display preference of the field.display_preference properties1 propertyhiddenbooleanOptionalIndicates whether to show or hide the field.