Some Ingenico transactions are approved by the donor’s bank, get past our fraud filters, but are then rejected by the donor’s bank. They reach Civi and look like real donations, even though they never settle (do we really get the funds?).
I found them by searching for Status 190 transactions, and two recent examples are: 1. Ingenico Order ID 4010135034 from cid=51163817, and 2. Ingenico 4010140171 from cid=50378878. We have seen 35 this year, all from JCB cards in Japan, and a total of 11 in 2019-20, but 120 in 2018, from a mix of card types.
This is not a huge volume of transactions, so I will leave the prioritization to the wider group of stakeholders, but I wanted to flag this as it looks like a type of not-real donations in Civi. I can put the spreadsheet of transactions on the server if it would be helpful. {T202783} seems related to how the recurring donation flow handles these, but the older ones I have spot-checked included one-time donations as well.