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

Enlarge / Someone really likes Google Chrome.

Google Chrome is shutting down its oldest and most capable extension system, Manifest V2, in favor of exclusive use of the more limited Manifest V3. The deeply controversial Manifest V3 system was announced in 2019 and the full change was delayed a million times over, but now Google says it will actually make the transition: As previously announced, the phasing out of older Chrome extensions will begin next week . .

Google Chrome has been working on a plan for a new, more limited extension system for a while now. Google says it created “Manifest V3” extensions with the goal of “improving the security, privacy, performance, and reliability of the extension ecosystem.”

Other groups disagree with Google’s description, such as the Electronic Frontier Foundation (EFF), which called Manifest V3 “misleading and threatening” when it was first announced in 2019, saying the new system “will restrict the capabilities of web extensions”. especially those that are designed to monitor, modify, and calculate along with the conversation your browser has with the websites you visit.” He has an entire article detailing how Manifest V3 won’t help security.

Comments from the Firefox team have also cast doubt on Google’s justification for Manifest V3. In a talk about the implications of Manifest V3, Philipp Kewisch, director of add-on operations at Firefox, said: “As for malicious add-ons, we believe that Firefox has been at a manageable level and, given that add-ons are more interested in capture data, they can still do it with 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 compatible with all browsers, but it has no plans to disable support for Manifest V2.

A big source of skepticism around Manifest V3 is the limitations around “content filtering,” aka the APIs that ad blockers and anti-tracking extensions use to fight advertising companies. like google. Google, which makes about 77 percent of its revenue from advertising, hasn’t released a serious explanation for why Manifest V3 limits content filtering, and it’s unclear how that aligns with goals of “improving security, privacy, performance and reliability. “As Kewisch said, the main goal of malicious extensions is to spy on users and suck data, which has nothing to do with content filtering. All of this is happening while Google is building an advertising system directly into Chrome, and Google properties like YouTube are cracking down on ad blockers.

The initial version of Manifest V3 was detailed in 2019 and since then, Google has gone back and forth with the extensions community and made some concessions. Google says it increased the number of filtering rule sets allowed by Manifest V3, which should help ad blockers. One dramatic change is that filtering extensions will no longer be able to update their rule sets on their own, and any filtering update would require submitting a new version to the Chrome Extension Store, including a security review that could last weeks. In the cat-and-mouse game of ad blockers, you can imagine how this could allow YouTube to change the ad system instantly, while any counterattack by ad blockers could be delayed for weeks. Google now says it’s possible for extensions to bypass the review process for “safe” ruleset changes, but even this is limited to “static” rulesets, not the more powerful, “dynamic” ones.

In a comment to The Verge last year, EFF senior technologist Alexei Miagkov summed up Google’s public negotiations with the extension community well, saying: “These are useful changes, but they are adjustments to a system limited by design “. The big problem remains the same: if extensions can’t innovate, users lose and trackers win… Now we all depend on Google to continue evolving the API to keep up with advertisers and trackers.”

Google says: “more than 85% of actively maintained extensions in the Chrome Web Store run Manifest V3, and all major content filtering extensions have versions of Manifest V3 available.” The company does not mention that the Manifest V3 version of the most popular ad blocker is “uBlock Origin Lite”, and “Lite” indicates that it is inferior to the Manifest V2 version.

As for how this removal will play out, Google says that next week beta versions of Chrome will start seeing warning banners on the extensions page for any Manifest V2 extensions they have installed. V2 extensions will also lose their “featured” status in the Chrome Extension Store. Google says the extensions will begin to be disabled in “the coming months.” For a short period, users will be able to turn them back on by visiting the extension page, but Google says that “over time, this option will also disappear.” At that point, you can search for alternatives in the Chrome Store or switch to Firefox.

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