Show payment instructions in the order receipt

Any patch for Drupal 9?

I tested the patch #21 in Drupal 10 and it is working. Thank you!

I'd like to add that this feature is really important. When using manual payments like a bank transfer, where you provide the bank account details and the reference-number, it is important that all those payment details are within the mail and not just once on the website. I consider it a must-have.