The Application Cache, also known as AppCache, is deprecated.
How the Lighthouse Application Cache audit fails
Lighthouse flags pages that use the Application Cache:
This audit fails when Lighthouse finds a reference to the Application Cache manifest in a page's
<html> tag. For example, this markup causes the audit to fail:
Each Best Practices audit is weighted equally in the Lighthouse Best Practices Score. Learn more in The Best Practices score.
Use the Cache API instead of the Application Cache
To migrate from the Application Cache to service workers, consider using the sw-appcache-behavior library. This library generates a service-worker-based implementation of the behavior defined in an Application Cache manifest.
See the Current page does not respond with a 200 when offline post for more information about using service workers to make your site work offline.
- Source code for Uses Application Cache audit
- MDN's Cache page
- Current page does not respond with a 200 when offline