[w3c/payment-handler] Missing question mark, (#163)

is 
[Exposed=ServiceWorker]
interface PaymentRequestEvent : ExtendableEvent {
    ...
    Promise<WindowClient> openWindow(USVString url);
   ...
};
should be
[Exposed=ServiceWorker]
interface PaymentRequestEvent : ExtendableEvent {
    ...
    Promise<WindowClient?> openWindow(USVString url);
   ...
};
to allow return null

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/w3c/payment-handler/issues/163