Manifest v2 Chrome extensions will stop working in June 2023
Google has been working on a new extension manifest, Manifest v3, for quite some time. The company introduced support for the new manifest version in Chrome 88, released earlier in 2021, and has now revealed plans to phase out support for extensions that use Manifest v2.
According to the timeline that Google posted, Chrome's Web Store will block new Manifest V2 extensions from being accepted from January 17, 2022 onward. Updates for existing Manifest V2 extensions can still be submitted and these will be updated normally. Private extensions, those with the private visibility setting, can still be submitted as Manifest V2 extensions.
In June 2022, private extensions will no longer be accepted as well. Updates for existing Manifest V2 extensions are still allowed.
In January 2023, Chrome will no longer accept Manifest V2 extension updates in the Chrome web browser. Google's web browser will stop running Manifest V2 extensions, but there is an Enterprise policy which extends support by six months.
In June 2023 finally, that Enterprise policy is removed and any version of Google Chrome won't run Manifest V2 extensions anymore.
The blocking of Manifest V2 extensions in Chrome has a significant impact on the Chrome browser's extensions ecosystem. Developers need to update their extensions to make them compatible with Manifest V3. Any extension that is not updated, e.g. because it has been abandoned by its developer, or can't be upgraded because of changes, won't be compatible with Chrome in 2023.
Many Chrome extensions will stop working, and the situation may remind Firefox users of a time when Mozilla switched the browser's extensions system. Many stopped working, because they were not updated or could not be, and Mozilla purged these from its store in the end. Google will likely do the same with Manifest V2 extensions in the Chrome Web Store, as these serve no purpose anymore for the company and could frustrate users.
Google has been criticize heavily for the initial Manifest V3 drafts, as these changed core content blocking API functionality. Several extension developers, including Raymond Hill, who developers uBlock Origin, voiced their concern over the drafts that Google published at the time. Hill stated back then that Manifest V3 could be the end of uBlock Origin for Google Chrome.
Google updated the Manifest V3 draft several times since it published the initial proposal. It is too early to tell whether these changes are sufficient, or if some types of extensions will launch with limited functionality or not at all when Manifest V3 is made mandatory in the browser.
In the meantime, we will continue to add new capabilities to Manifest V3 based on the needs and voices of our developer community. Even in the last few months, there have been a number of exciting expansions of the extension platform. We introduced additional mechanisms to the new Scripting API, and we expanded the Declarative Net Request API with support for multiple static rulesets, filtering based on tab ID, and session-scoped rules.
The change will impact other Chromium-based browsers. Developers of these browsers face a predicament: if they follow Google, they may introduce the same limitations in their browsers. If they don't, they have to find a way around it, either by continuing to support Manifest V2 extensions and making sure that these can be updated and downloaded, or through other means.
Mozilla is in a better position. The organization stated in 2019 that it won't follow Google in limiting APIs in Manifest V3.
Developers of extensions can check the official support page on Google's Developer site for updates.