Basic PayPal Checkout button giving 500 internal server errors in Firefox

Question

I am using the Basic PayPal Checkout Button (data-version-4) with a jason payload to make a payment against the sandbox. All code works fine until it reaches the point “Confirm” or “Pay now” in the PayPal pop-up window (Lightbox) ... at this moment the pop-up window closes and further calls to the button (for example: onAuthorize is not initiated).

At this point, the console shows several warnings and errors after 3 x apy_retry. Is this a known issue or does anyone have a suggestion on this?

Any help is appreciated and thanks in advance, Christian

UPDATE: in Google Chrome (version 54) you can make a payment, I have errors only in Firefox V49.0.2

Attention

missing_csrf_jwt Object { timestamp=1479294755397, windowID="5fbc81d2c8", pageID="3768daa62d"}

Error

"NetworkError: 500 Internal Server Error - https://www.sandbox.paypal.com/webapps/hermes/api/payment/PAY-1UH37573M6748251ALAWD6BI?"

http_response_500 Object { timestamp=1479294756872, windowID="5fbc81d2c8", pageID="3768daa62d"}

GET payment request response to button.js

{"ack":"error","message":"Unhandled api error","meta":{"calc":"5c86b8d3140ef","rlog":"rKGmcXTB%2B2NqZAMhrf0E %2BSi2kRuzAYN1zBd6UkYGjcFtNQ0WfaI3FHIbPIRTaJRcwP4CM4%2FkeW05efr7awS8xw_1586cc53450"},"server":"Wb_7k zG8hs8iXSTxTssRX7gAbhKsGUveN-Qi5qR4xO-eChao8SHpy7dW9-lcr1X7z1Ex578DclpDjpNeK6E56fHpDAqRWL8SI0Od4rpHe HT57pjggRD85TXSwGA9IYgdTw8WLisakLokxa9yxvmsjiYYO9Sf8Hnb4sanRFuPznDh8b4zEXUgz2kxautGGtS3lTXJjgK9TVqouGCqrStk_j4GQC1ssToOZ0n6am" }

Console

Screenshot with Dev Tools Console

Answer 1

The developer console says (in my opinion, in German) there is a problem with Strict-Transport-Security. This is almost certainly your problem, because the policy for handling this error is different from the browser by the browser.

I also see that the Paypal API is on the https address. Is the request coming from your browser in the http settings (without s)? This may be a problem in this case, since you want the request for a secure API to also come from an encrypted, secure source.

EDIT: LetsEncrypt, , , , SSL-.