Google Chrome's big extension update could break ad blockers — what we know

Laptop computer displaying logo of Google Chrome, a cross-platform web browser developed by Google.
(Image credit: Shutterstock)

Starting in January 2023, Google will begin phasing out the Manifest V2 Chrome extension platform as it shifts to Manifest V3. While Google says this new platform will provide better security, the new Chrome extension rules could hobble ad blockers.

As detailed in a blog post by Product Manager at Google, David Li, Google may start turning off support for Manifest V2 extensions in Canary, Dev and Beta channels with Chrome 112. Then in June with Chrome 115, the company will start turning off support for Manifest V2 extensions in all channels, including the stable channel.

“Chrome will take a gradual and experimental approach to turning off Manifest V2 to ensure a smooth end-user experience during the phase-out process,” said Li. In addition, the company is making sure that developers have all the information they require and that they’ll be given “plenty of time” to transition to Manifest V3 and roll out changes to users.

Manifest V2 won’t completely go away in 2023 as Google is extending Manifest V2 support to January 2024 for enterprise users. Google has also added a progress page for those interested in keeping track of in-progress feature additions and bug fixes to Manifest V3.

The controversy surrounding Manifest V3

Manifest V3 was first announced in 2019, with beefier security being a major component of the Chrome browser extension framework. This is a legitimate concern seeing as how malicious browser extensions have been running rampant in the Chrome Web Store over the past few years.

Though Google seems to have been doing a better job of policing extensions, many of the extensions abused the powers they held under Manifest V2 to spy on users and steal sensitive information.

Experts like senior staff technologist at the Electric Frontier Foundation, Alexei Miagkov, aren’t convinced this is about user security or privacy. "Our criticism still stands," said Miagkov to The Register. "The reasons they have stated publicly [for this transition] don't fully make sense."

In 2019, Miagkov was co-author of an EFF report that said "Manifest V3 is a blunt instrument that will do little to improve security while severely limiting future innovation." One widely used browser extension that likely won't work under Manifest V3 is the EFF's own Privacy Badger, which blocks web trackers.

Google Chrome on macOS

Some experts question Google's claims that Manifest V3 will improve security on Chrome. (Image credit: Shutterstock)

An annual report Google filed in early 2019 with the U.S. Securities and Exchange Commission (SEC) stated that ad-blocking technology could affect Google’s revenue. Google also pays Adblock Plus to whitelist its online advertising, and Adblock Plus appears to conform to Manifest V3.

Around the same time, Raymond Hill, who maintains the free uBlock Origin and uMatrix ad blockers, posted in a Chromium developers' forum that Manifest V3 meant that his two ad blockers could "no longer exist." For those who may not know, Chromium is the open-source platform on which Chrome and many other browsers are built.

Simeon Vincent, a developer advocate for Chrome Extensions, said later in 2019 that Manifest V3 would not disable ad blockers but would instead let developers make better ad blockers.


It's not clear how much money Google and publishers lose because of ad blockers, but the company’s claim that Manifest V3 will help developers create better ad blockers seems somewhat unlikely, at least based on what some experts have said.

Many ad blockers and privacy extensions may stop working on Google Chrome, but rival browsers could continue supporting them. Firefox maker Mozilla says it will support Manifest V3 but also let ad blockers work; Microsoft has implied it will do the same in Edge. Brave, like Edge, is Chromium-based but says it blocks ads (by default) at a deep level that won't be affected by Manifest V3.

Presently, Google Chrome has a grip on about two-thirds of the global desktop browser market, according to StatCounter. If ad blockers no longer work on Google’s platform, it could give rivals a chance to grab a bigger piece of the market. We’ll keep you updated on Manifest V3’s rollout as it unfolds in 2023.

Read next: Google Chrome might not be as secure as you'd previously hoped

Tony Polanco
Computing Writer

Tony is a computing writer at Tom’s Guide covering laptops, tablets, Windows, and iOS. During his off-hours, Tony enjoys reading comic books, playing video games, reading speculative fiction novels, and spending too much time on X/Twitter. His non-nerdy pursuits involve attending Hard Rock/Heavy Metal concerts and going to NYC bars with friends and colleagues. His work has appeared in publications such as Laptop Mag, PC Mag, and various independent gaming sites.