Here is a neutral and interesting 1-paragraph summary of the text: Using the Background Sync API from Service Workers, developers can replicate the behavior of sending SMS messages in the background even when the user is offline. By registering a Service Worker, intercepting form submit events, saving messages to IndexedDB, and implementing the sync event, developers can create network resilient message sending that allows users to send messages without keeping the web application open. With this implementation, users can receive their sent messages immediately upon reconnecting to the internet, providing a seamless user experience similar to native applications.