I use a password manager to also fill in forms, including credit card numbers. I accidentally selected the wrong credit card from the list and hit to submit the payment. In less than 1 second after hitting Submit, before the screen had even changed, I realized, but there was literally no way to stop it. I needed to contact the seller and ask them to refund the payment and reissue the invoice. A hassle for everyone. If there had just been a few seconds or minutes window after I entered the payment, but before the transaction posted, and a button to undo or make changes, it would solve all of these kinds of problems.