Overview and timelines for migrating to Manifest V3

A manifest file is the blueprint of an extension. A manifest file for an extension includes information such as the version number of the extension, the title of the extension, and permissions needed to run the extension. The manifest file follows the format specified by Manifest V2 or Manifest V3.

Overview of changes in Manifest V3

Migrating from Manifest V2 to Manifest V3 brings several structural changes to how extensions are handled by the browser.

In October 2020, Microsoft announced the decision to embrace Manifest V3 to help reduce fragmentation of the web for all developers and enhance privacy, security, and performance for end users.

Manifest V3 is an initiative of the Chromium project.

An overview of the changes involved, as described in Migrate to Manifest V3:

  • Background pages have been replaced by service workers.

  • Network request modifications are now handled by the new declarativeNetRequest API.

  • Remotely hosted code is no longer allowed. An extension can only run JavaScript that's included within its own package.

  • Support for Promises has been added to many methods. Callbacks are still supported, as an alternative.

  • Various minor feature improvements.

Manifest timeline for the Chromium browser engine

Chromium has revised the timelines for ending support for Manifest V2. See:

Manifest timeline for Microsoft Edge and Partner Center

To help you plan the migration of your extension from Manifest V2 to Manifest V3, consider the following schedule for support for Manifest V2 and V3 in Microsoft Edge and Microsoft Partner Center.

The Microsoft Edge team will independently decide on MV3 migration timelines for Microsoft Edge Add-ons and share an update here. We continue to analyze the concerns raised by extension developers and explore the optimal path for the Microsoft Edge Add-ons ecosystem. Meanwhile, to plan the migration of your extension from Manifest V2 to Manifest V3, see Manifest timeline for the Chromium browser engine, above.

The Microsoft Edge team is currently in the process of updating this MV3 migration timeline.

Timeframe Microsoft Partner Center changes Microsoft Edge changes
July 2022 (already in effect) Microsoft Partner Center will no longer accept new Manifest V2 extensions with visibility set as Hidden or Public. No change.
TBD Microsoft Partner Center will no longer accept updates to existing Manifest V2 extensions. Developers can submit updates for migrating a V2 extension to V3. Microsoft Edge stops running Manifest V2 extensions. Enterprises can allow Manifest V2 extensions to run on Microsoft Edge, by using enterprise policies.
TBD No change. Manifest V2 extensions will no longer function in Microsoft Edge, even with the use of enterprise policies.

Manifest V2 extensions will continue to be supported through Enterprise policies at least until the date in the Chromium Manifest V2 support timeline.

Microsoft continues to iteratively improve the platform and address the feedback shared by extension developers. Share your questions, comments, and concerns with the team on Twitter @MSEdgeDev or via the Microsoft Edge Insider forums on TechCommunity.

See also