Is Google really Killing Ad Blockers?
New study shows the actual impact of Google’s Manifest Version 3 update on ad blocker effectiveness
Google’s recently rolled out Chrome Manifest Version 3 (MV3) update faced intense criticism and was widely dismissed as “killing ad blockers”. Critics raised concerns about Google’s influence on online transparency and the potential consequences for user privacy. In response to this backlash, Google implemented significant changes to the MV3 framework that provided relief to ad blocker developers. A new study finds that the update ultimately has minimal impact on ad blocking effectiveness. Most ad blocking extensions remain as effective as before, with only minor limitations.
In December 2020, Google introduced Manifest Version 3, an update to how Chrome browser extensions operate. Google positioned the change as a strategy to improve user privacy, security, and browser performance. However, ad blocker providers and privacy advocates warned that the update would severely restrict the ability of ad blockers to protect users from unwanted advertisements and online tracking. Some critics even described the update as “killing ad blockers”. These concerns were often linked to Google’s dual role as a browser provider and a leading online advertising company.
To empirically assess these claims, TRR 266 researcher Lazaros Papadopoulos and his co-author Karlo Lukic from Goethe University Frankfurt conducted a large-scale browser-based study comparing the performance of ad blockers before and after the transition to MV3. They tested four widely used ad blockers: Adblock Plus, AdGuard, Stands, and uBlock Origin. Each browser was tested in both MV2 and MV3 versions across approximately 924 websites.
The findings challenge the widespread perception that the update would weaken ad blockers. Papadopoulos explains: “Our results show that the MV3 instances of popular ad blockers continue to provide effective protection against intrusive ads and privacy-infringing trackers.” In fact, when measuring protection against online trackers, the newer versions sometimes even performed better than their Manifest Version 2 counterparts.
These findings offer reassurance to the millions of internet users who rely on ad blockers for privacy and a cleaner browsing experience. Ad blocker providers appear to have found effective solutions to adapt to the new framework. While the visual appearance of websites may show minor differences in some cases due to incomplete cosmetic filtering, the fundamental ability to block ads and protect against tracking remains intact. The research suggests that users can continue to depend on their preferred ad blockers during and after Google’s transition period.
The study has been published in the first 2026 issue of the Proceedings on Privacy Enhancing Technologies (PoPETs), a leading peer-reviewed venue for privacy research.