PayPal sandbox testing

PayPal offers "sandbox" accounts, allowing you to test the entire purchase flow without actually paying anything. In the PayPal Developer Center, one creates both a personal and a business sandbox account - the business account is to be used by the store and the personal account you use when testing a purchase. Great. But when I try to "Connect" to PayPal using the business sandbox account, it doesn't recognize it as existing and thinks I am creating a new account.

Is there some trick I am missing here? I am a bit astonished not to have found another thread here on the topic.

This is because the PayPal integration used by Squarespace is very old and is due for an update. PayPal offer a range of excellent features but many of these are not yet available on Squarespace. We're hoping these will be added in 2021.

If you want to test PayPal on the Squarespace checkout, you must place a real order and then refund yourself. Note that you will only receive a partial refund from PayPal because they will withhold the fixed transaction fee, (for example, $0.30 for U.S.-based accounts).

Thanks - I knew about the refund thing and not refunding the fee. I was hoping there was a better way.