Manifest V3 is the latest version of the extensions platform. We have made a number of changes to the available APIs and added a number of new features.

Our Goals

Manifest V3 aims to be the first step in our platform vision to improve the privacy, security, and performance of extensions. Along with the platform changes, we are working to give users more understanding and control over what extensions are capable of. The changes will take several years to complete.

What changes?

Extensions in Manifest V2 had a long-lived background page that took up resources, even when an extension wasn't running. In Manifest V3, we have moved the background context to service workers, which run only when needed.
Manifest V3 removes the ability for an extension to use remotely hosted code, which presents security risks by allowing unreviewed code to be executed in extensions. With this change, an extension can only execute JavaScript that is included within its package and subject to review by the Chrome Web Store.
We are deprecating the blocking version of the webRequest API. This required extensions to proxy all network traffic to provide filtering capabilities, which came at a performance and privacy cost. The new declarativeNetRequest API provides a safer alternative for many use cases.
Manifest V3 also adds a number of new APIs and capabilities, improvements to the platform including support for promise-based methods, and more.

Where to go from here?

Learn to migrate your extension.
See key platform gaps we closed as part of the transition.
See a checklist of changes for migration.
Advice on publishing an updated extension.