Service Workers & Progressive Web Apps

What is the role of background sync in Service Workers?

registration.sync.register('sync-posts').then(() => {
  console.log('Sync registered');
});

self.addEventListener('sync', event => {
  if (event.tag === 'sync-posts') {
    event.waitUntil(
      syncPosts().catch(err => {
        console.error('Sync failed:', err);
      })
    );
  }
});

To synchronize multiple Service Workers
To keep the Service Worker running
To defer actions until network is available
Background sync allows web apps to defer actions until the user has stable network connectivity. This is particularly useful for: 1) Ensuring data is sent to the server even if the user goes offline, 2) Implementing offline-first functionality, 3) Improving reliability of data submission, 4) Providing better user experience in poor network conditions.
To update the cache periodically

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