Ad blockers may become obsolete as a result of major changes coming to Chrome

Chrome extensions and web store product manager David Li recently announced that as of January 17, 2022, extensions built using the Manifest V2 specification will no longer be accepted on the web store. Furthermore, in January 2023, all Manifest V2 extensions will be deactivated, so any that you have installed will no longer work.

"Years in the making, Manifest V3 is more secure, performant, and privacy-preserving than its predecessor," Li wrote. "It is an evolution of the extension platform that takes into consideration both the changing web landscape and the future of browser extensions." says the company.

It is also significant for another, and for many Chrome users, far more practical, reason: According to TechRadar, the loss of Manifest V2 means that ad blockers that many Chrome users have become accustomed to will no longer work. Current ad blockers use a specific API that Manifest V3 deprecates, and there is debate over whether new ad blockers can or will be built using the new Manifest V3 specification.

Google said in a 2019 Chromium blog post that disabling ad blockers is "absolutely not the goal" of the new spec. "In fact, this change is meant to give developers a way to create safer and more performant ad blockers," Chrome extensions developer advocate Simeon Vincent wrote at the time.

However, Google parent company Alphabet explicitly warned in a 2018 SEC filing that ad blocking technology, both old and new, has the potential to harm its 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," according to the filing. "The majority of our Google revenue comes from fees paid to us in connection with the online display of advertisements. As a result, these technologies and tools may have a negative impact on our operational results."

The Electronic Frontier Foundation disputed Google's claims, saying in a statement released in 2019 that while the Manifest V3 standard may not be specifically aimed at killing ad blockers, it could easily happen as a result of the new API's limitations on developers.

"For developers of ad- and tracker-blocking extensions, flexible APIs aren’t just nice to have, they are a requirement," the EFF wrote. "When particular privacy protections gain popularity, ads and trackers evolve to evade them. As a result, the blocking extensions need to evolve too, or risk becoming irrelevant ... If Google decides that privacy extensions can only work in one specific way, it will be permanently tipping the scales in favor of ads and trackers."

Senior staff technologist Alexei Miagkov, who co-authored that post, told The Register that the EFF's position on the new Manifest V3 standard, and Google's justification for it, hasn't changed. "Our criticism still stands," he said. "The reasons they have stated publicly [for this transition] don't fully make sense."

Google promised to share more information about the transition to Manifest V3 in Chrome as the rollout date approaches, and that it will continue to add new features "based on the needs and voices of our developer community." The Chrome Developers site has a detailed timeline for the Manifest V2/V3 transition.

Even if Google does remove ad blockers as we know them from Chrome, extension developers will most likely find workarounds to allow users to continue to avoid ads.