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Browser Service Worker Errors — Registration, Cache & Update Failures

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About Browser Service Worker Errors

Fix Service Worker errors including registration failure, stale cache serving old content, update stuck in waiting state, and scope misconfiguration. This guide covers everything you need to know about this topic, including common causes, step-by-step solutions, and answers to frequently asked questions.

Here are the key things to understand: Service Workers are background scripts that intercept network requests for offline functionality. Registration requires HTTPS (or localhost for development). A common issue: new code deployed but users still see old cached version. Service Workers have a lifecycle: install > waiting > activate > running. DevTools > Application > Service Workers shows the current state and allows manual control. Understanding these fundamentals will help you diagnose and resolve this issue more effectively.

The most common reasons this occurs include: Service Worker not registering: not served over HTTPS, or JS syntax error in SW file. Stale content: old Service Worker still serving cached responses from previous deployment. Update stuck in waiting: new SW waiting for all tabs to close before activating. Cache strategy too aggressive: caching responses that should not be cached. Scope too narrow: SW only controls pages within its scope path. Identifying the root cause is the first step toward finding the right solution.

To resolve this, follow these recommended steps: Check registration: DevTools > Application > Service Workers — look for errors in status. Force update: check 'Update on reload' in DevTools Service Workers panel. Skip waiting: in SW code, call self.skipWaiting() in the install event. Clear all caches: DevTools > Application > Cache Storage > right-click > Delete. Unregister SW: DevTools > Application > Service Workers > Unregister, then hard refresh. If these steps do not resolve the issue, consider consulting additional resources or a qualified professional.

This article is part of our Browser Errors collection on Error Codes Wiki. We provide comprehensive, up-to-date information to help you find solutions quickly.

Quick Answer

Why are users seeing old content after deployment?

The old Service Worker is still serving cached responses. Implement a proper cache versioning strategy and use skipWaiting() to activate new SW immediately.

Overview

Fix Service Worker errors including registration failure, stale cache serving old content, update stuck in waiting state, and scope misconfiguration.

Key Details

  • Service Workers are background scripts that intercept network requests for offline functionality
  • Registration requires HTTPS (or localhost for development)
  • A common issue: new code deployed but users still see old cached version
  • Service Workers have a lifecycle: install > waiting > activate > running
  • DevTools > Application > Service Workers shows the current state and allows manual control

Common Causes

  • Service Worker not registering: not served over HTTPS, or JS syntax error in SW file
  • Stale content: old Service Worker still serving cached responses from previous deployment
  • Update stuck in waiting: new SW waiting for all tabs to close before activating
  • Cache strategy too aggressive: caching responses that should not be cached
  • Scope too narrow: SW only controls pages within its scope path

Steps

  1. 1Check registration: DevTools > Application > Service Workers — look for errors in status
  2. 2Force update: check 'Update on reload' in DevTools Service Workers panel
  3. 3Skip waiting: in SW code, call self.skipWaiting() in the install event
  4. 4Clear all caches: DevTools > Application > Cache Storage > right-click > Delete
  5. 5Unregister SW: DevTools > Application > Service Workers > Unregister, then hard refresh

Tags

browserservice-workercachepwaoffline

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Frequently Asked Questions

The old Service Worker is still serving cached responses. Implement a proper cache versioning strategy and use skipWaiting() to activate new SW immediately.