Google Chrome’s plan to restrict ad-blocking extensions starts next week

Google Chrome will disable its older, more powerful extension system, Manifest V2, in favor of exclusively using the more limited Manifest V3. The highly controversial Manifest V3 system was announced in 2019, and the full transition has been delayed a million times, but now Google says it will actually make the transition: As previously announced, it will begin phasing out legacy Chrome extensions next week.

Google Chrome has been working on a plan for a new, more limited extension system for some time now. Google says it created “Manifest V3” extensions to “improve the security, privacy, performance, and trustworthiness of the extension ecosystem.”

Other groups disagree with Google’s description, such as the Electronic Frontier Foundation (EFF), which already called Manifest V3 “deceptive and threatening” at the time of its 2019 announcement, saying the new system would “limit the capabilities of web extensions— especially those that are designed to monitor, modify and calculate as your browser talks to the websites you visit. Contains an entire article detailing how Manifest V3 will not help with security.

The Firefox team’s comments also cast doubt on Google’s rationale for Manifest V3. Speaking about the implications of Manifest V3, Philipp Kewisch, manager of add-on operations at Firefox, said: “We believe this is at a manageable level for malicious add-ons on Firefox, and since add-ons are mostly interested in capturing data, we still they can do this using the current web request API (in Manifest V3).” Firefox plans to support Manifest V3 because Chrome is the most popular browser in the world and wants extensions to be cross-browser compatible, but has no plans to disable support for Manifest V2.

A big source of skepticism about Manifest V3 is its restrictions on “content filtering,” which are the ad-blocking APIs and anti-tracking extensions used to fight ad companies like Google. Google, which generates about 77 percent of its revenue from advertising, has not released a serious explanation for why Manifest V3 limits content filtering, and it is unclear how it is for the purposes of “improving security, privacy, performance and trustworthiness.” ” As Kewisch said, the main purpose of malicious extensions is to spy on users and scrape data, which has nothing to do with content filtering. All of this is happening as Google builds an ad system directly into the Chrome browser, and Google services like YouTube take aggressive actions against ad blockers.

The initial version of Manifest V3 was detailed in 2019, and since then Google has engaged with the extension community and made some concessions. Google says it has increased the number of filter rule sets allowed by Manifest V3, which should help with ad blocking. One dramatic change is that filtering extensions will no longer be able to update their rulesets themselves, and any filtering updates will require a new version to be uploaded to the Chrome extension store, which includes a potentially week-long security check. In the cat-and-mouse game of ad blockers, you can imagine how this could allow YouTube to change its advertising system immediately, while any counterattack from ad blockers could be delayed for weeks. Google now says extensions can bypass the process of checking for “safe” rule set changes, but even this is limited to “static” rule sets, not the more powerful “dynamic” ones.

In a commentary for The Verge last year, EFF senior staff technologist Alexei Myagkov nicely summarized Google’s public negotiations with the extensions community, saying: “These are helpful changes, but they are improvements to a design-constrained system. The core problem remains the same: if extensions can’t innovate, users lose and trackers win. Now we all rely on Google, which is constantly evolving its API to keep up with advertisers and trackers.

Google says that “over 85% of actively maintained extensions in the Chrome Web Store use Manifest V3, and all of the best content filtering extensions are available on Manifest V3 versions.” The company fails to mention that the most popular version of the Manifest V3 ad blocker is “uBlock Origin Lite”, with “Lite” meaning it is inferior to the Manifest V2 version.

As for how this rollback will actually happen, Google says that next week, beta versions of Chrome will begin displaying warning banners on the extensions page for any Manifest V2 extensions you have installed. Extensions in version 2 will also lose their “recommended” status in the Chrome extension store. Google says extensions will begin to be disabled in the “coming months.” For a short time, users will be able to re-enable them if they visit the extension’s page, but Google says “this feature will also disappear over time.” At this point you can either look for alternatives in the Chrome store or switch to Firefox.