Service worker support after a system update

After a system update, an offline page may stop loading, a website may repeatedly reload, or an app may say service workers are unavailable. That does not automatically mean your browser lost support. The update may have changed the browser version, profile settings, or how the site registers its worker.

Start by checking what your browser supports, then compare that result with the conditions the affected website needs. The Browser Info tool shows your browser version, engine, permissions, and supported features.

Check service worker support

1. Open Browser Info in the browser where the problem occurs.
2. Check the browser version and engine shown in the report. Note them down so you can compare after updating or testing another browser.
3. Review the supported-features results for service worker support. The report checks browser capability, not whether a particular website has successfully installed a worker.
4. Open the affected website in a regular browser tab, using its full HTTPS address. If the site has an offline feature, load it while online before testing that feature.

Test in the same browser profile and on the same device where the issue appears. A result from a different browser or computer may not explain what changed after your update.

What the result means

Service worker support is available

Your browser exposes the feature. The problem is more likely specific to the website, its connection, or the browser profile than a complete loss of browser support. A service worker is a small script a site can use for tasks such as caching pages or supporting offline use. The site still has to register and install it correctly.

Service worker support is unavailable

The browser or the context it is running in does not expose the feature to the test. Check that the browser is current and that you are using a regular, secure page. If the result stays unavailable in an up-to-date browser, a managed policy or unusual browser configuration may be restricting it.

Support is available, but only one site fails

That points toward a site-specific issue. Service workers require a secure context, normally an HTTPS page. The local address localhost is also treated as secure for development. A page opened over plain HTTP, or a different address than the one the site expects, may not be able to register its worker.

Remember that a service worker is not the same as a browser permission such as camera or microphone access. It normally does not trigger a permission prompt. For a broader explanation of support and site requirements, see service worker support in a browser.

How to fix it

1. Reload the affected site and restart the browser. Close all browser windows, reopen the browser, and visit the site again. If the browser updated in the background, a restart may be needed before the new version is active.
2. Check the address and secure connection. Use the site's normal HTTPS address and make sure the browser does not show a certificate warning. A certificate problem can stop the browser from treating the page as secure. For local development, use localhost rather than a plain HTTP address on the network.
3. Update the browser itself. A computer's operating system update does not always update every browser. In Chrome on Windows, open Menu › Help › About Google Chrome. On macOS, use Chrome › About Google Chrome. In Edge, open Settings and more › Help and feedback › About Microsoft Edge. In Firefox, open Help › About Firefox. On macOS, Safari updates are included with macOS updates, available under System Settings › General › Software Update.
4. Try a regular window and a clean profile. Private browsing can use different storage rules, and extensions can interfere with a site's scripts or storage. Test the page in a regular window. If it works in a new browser profile, review extensions and privacy settings in the profile that fails rather than turning off protections everywhere.
5. Reset data for the affected site only. If the site has an outdated or damaged local registration, clearing that site's stored data may let it start fresh. This can sign you out or remove saved preferences, so keep any information you need first. Use the browser's site data or site settings controls, then revisit the HTTPS address.
6. Check for managed browser restrictions. On a work or school device, an administrator may control browser features or site storage. If support is available in one profile or browser but not the managed one, ask the administrator before changing policies. On Windows 11, check for pending system updates at Settings › Windows Update. On a Mac, check System Settings › General › Software Update.

What the browser test cannot confirm

A browser feature check can tell you whether the browser reports service worker support. It cannot confirm that the site's code registered a worker, that its server delivered the right files, or that its offline cache contains the page you need. A working feature report alongside a failing website is useful evidence to share with that site's support team.