When attempting to authorize an Apple Payment on an iOS 18 device using the scannable code in a non-Safari browser (i.e. Chrome), the payment sheet displays briefly, then dismisses.
This same exact implementation of Apple Pay on the Web works flawlessly in Safari, so this feels like a bug given that the merchant session works fine in Safari.
The following errors were found in my iOS device logs:
(PassbookUIService) Codable: Failed to decode Merchant Session Created: Error Domain=NSCocoaErrorDomain Code=4864 UserInfo={NSDebugDescription=<private>, NSCodingPath=<private>}
(PassbookUIService) Session 29592: Fatal Error: Failed to decode merchant session created`