Manage payment methods list missing

I have several saved cards in 152.0.1 (64-bit). When on a payment site the drop-down list shows up as expected, so the extensions.formautofill.creditCards.supportedCountries is correct and working (GB). Also address filling still works, as does saved passwords, However if I try to "Manage payment methods" the resulting list in "about:preferences#managePayments" is blank. (see image) I have tried toggling on and off "save & autofill" and restarting, but nothing helps. Adding a new card works, and the new card appears in the drop-down list on a payment form, but still nothing appears to edit or remove in the settings. How an I edit this list? PS: I have disabled ALL extensions.