Receipt without voucher

Hello,
If the customer chooses to pay by bank transfer and the option to send a confirmation is enabled, in the confirmation email he will receive a voucher for which he has not yet paid and the confirmation contains PAID.
After the payment is made and clicked in the administration, another payment email is then generated and an attachment with the voucher is sent to the final recipient’s address.
If the Direct email option is enabled, the voucher also goes to the final recipient without payment.
So the way to go is not to use direct mail, but I don’t understand how to get rid of the voucher attachment in the confirmation email.
Can you at least advise me which plugin script produces the emails?
Thank you
Michal

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