1455789 - Finalize option sorting and default selected index for the payment method picker

Status: RESOLVED DUPLICATE of bug 1494551

(Firefox :: WebPayments UI, enhancement)

Description

[Sam Foster [:sfoster] (he/him)]

PaymentMethodPicker currently displays options in the order they were added - i.e chronological order. So the most recently added (and possibly the most relevant) card appears at the bottom of the list. We may want to reverse this order, or sort by the record's timeLastModified property. 

When there is no existing selection (state.selectedPaymentCard) - or the previously selected entry has since been removed - we currently select the first (0th) option. Depending on how the list is sorted, that may not be the best UX.

If something like the paymentmethodchanged event[1] gets added to the spec, automatically selecting an option could trigger a side-effect where some credit card (methodName, methodDetails) are sent to the merchant as a result of the change event. This might be unexpected for the user if our guess at the best default doesnt match the card they want to use.

1. https://github.com/w3c/payment-request/pull/695

Comment 1

[Matthew N. [:MattN]]

The same problem also applies to address picker ordering and I think we may as well discuss them together.

Comment 2

[Matthew N. [:MattN]]

Sorting is bug 1494551 and paymentmethodchange (bug 1477113) was specified in a way that should avoid the surprise I think.