Google to restrict modern ad blocking Chrome extensions to enterprise users

Back in January, Google announced a proposed change to Chrome’s extensions system, called Manifest V3, that would stop current ad blockers from working efficiently. In a response to the overwhelming negative feedback, Google is standing firm on Chrome’s ad blocking changes, sharing that current ad blocking capabilities will be restricted to enterprise users.

Manifest V3 comprises a major change to Chrome’s extensions system, including a revamp to the permissions system and a fundamental change to the way ad blockers operate. In particular, modern ad blockers, like uBlock Origin and Ghostery, use Chrome’s webRequest API to block ads before they’re even downloaded.

With the Manifest V3 proposal, Google deprecates the webRequest API’s ability to block a particular request before it’s loaded. As you would expect, power users and extension developers alike criticized Google’s proposal for limiting the user’s ability to browse the web as they see fit.

Now, months later, Google has responded to some of the various issues raised by the community, sharing more details on the changes to permissions and more. The most notable aspect of their response, however, is a single sentence buried in the text, clarifying their changes to ad blocking and privacy blocking extensions.

Chrome is deprecating the blocking capabilities of the webRequest API in Manifest V3, not the entire webRequest API (though blocking will still be available to enterprise deployments).

Google is essentially saying that Chrome will still have the capability to block unwanted content, but this will be restricted to only paid, enterprise users of Chrome. This is likely to allow enterprise customers to develop in-house Chrome extensions, not for ad blocking usage.

For the rest of us, Google hasn’t budged on their changes to content blockers, meaning that ad blockers will need to switch to a less effective, rules-based system, called “declarativeNetRequest.”

One of the original concerns of switching to this system was the fact that Chrome currently imposes a limit of 30,000 rules, while popular ad blocking rules lists like EasyList use upwards of 75,000 rules. In the response, Google claims that they’re looking to increase this number, depending on performance tests, but couldn’t commit to anything specific.

We are planning to raise these values but we won’t have updated numbers until we can run performance tests to find a good upper bound that will work across all supported devices.

The lead developer of uBlock Origin, Raymond Hill, has commented on the situation, both to The Register and on uBlock Origin’s GitHub, pointing out that allowing ad blockers goes completely against Google’s business model.

Google’s primary business is incompatible with unimpeded content blocking. Now that Google Chrome product has achieve high market share, the content blocking concerns as stated in its 10K filing are being tackled.

Google themselves have even admitted as such in a recent SEC Form 10-K filing by Alphabet, uncovered by Hill, in which ad blocking extensions are labeled as a “risk factor” to Google’s revenues.

New and existing technologies could affect our ability to customize ads and/or could block ads online, which would harm our business.

Technologies have been developed to make customizable ads more difficult or to block the display of ads altogether and some providers of online services have integrated technologies that could potentially impair the core functionality of third-party digital advertising. Most of our Google revenues are derived from fees paid to us in connection with the display of ads online. As a result, such technologies and tools could adversely affect our operating results.

With that in mind, the change makes a great deal of sense, when you think of Chrome as a way for Google to better deliver ads to your devices. By allowing in-depth ad blockers to continue to function, they’re allowing for a direct, negative impact on their largest revenue stream. Chrome’s enterprise users get an exception, likely because they’re a separate revenue stream.


Update 5/30: A Google spokesperson has reached out to us with a statement, clarifying Chrome’s position on ad blockers and reiterating that they’re still working on Manifest V3 with the community.

Chrome supports the use and development of ad blockers. We’re actively working with the developer community to get feedback and iterate on the design of a privacy-preserving content filtering system that limits the amount of sensitive browser data shared with third parties.


9to5Google’s Take

Firefox is available on all platforms (including Chrome OS via the Android or Linux app) and, unlike Chrome, supports browser extensions on Android, including uBlock Origin and other privacy extensions. Just remember to unblock sites you wish to support financially.

This article has been updated to remove an inaccurate statement directly comparing declarativeNetRequest with AdBlock Plus and to add a link to information on Chrome Enterprise.


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