I've got a Magento 18.104.22.168 website running Paypal. If I try to activate Pay by Credit Card (Redsys, Adyen or whenever), this kind of payment doesn't work. The process stops on the code which calls pay platform, without any error message in any log file.
I've deactivated all plugins and OneStepCheckout, but when I try to pay with standard Checkout, I can only see steps 1 and 2, no more. And I still don't have any error message in log files.