[webpayments] Registration: App supports method but user has no instrument for that method (#110)

User registers a payment app that supports payment methods A, B, and C. But user does not register any payment instruments for method C. Merchant supports C.

Does browser match on C and display it, even though the user has no relevant payment instrument?
Should the payment app be prepared to deal with that scenario and inform the user (or invite the user to register a payment instrument)?

Should the browser not match on C?
Should there be other behavior?

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webpayments/issues/110