Google's push service returns a 201 status for all requests, regardless of whether the browser actually receives the notification, making it impossible to distinguish between successful delivery and silent failures. To address this, I implemented a receipt mechanism where the service worker confirms delivery back to the server using the subscription's auth secret. The application now tracks unconfirmed pushes per device and alerts users in the app settings if their device stops receiving notifications, providing clear instructions for manual resolution. Google Push says it sent, The user received nothing