Well.. it was ~6 years and ~10 billion payments ago, the clients have been fixed but the "hack" is still there, it has caused no harm as far as I can tell. Worst case scenario it's useless, best case scenario it prevents regressions.
The issue with things that client must not do is that they might still do them, and users don't care whose fault it is. It's important to have auxilliary mechanisms to mitigate these.
The issue with things that client must not do is that they might still do them, and users don't care whose fault it is. It's important to have auxilliary mechanisms to mitigate these.