Google's recent update to the manifest file for Chrome browser extensions-transitioning from manifest version 2 (MV2) to manifest version 3 (MV3)-has raised concerns among users and ad blocker providers, who worry that the new restrictions, notably the shift from the powerful WebRequest API to the more restrictive DeclarativeNetRequest API, might reduce ad blocker effectiveness. Because ad blockers play a vital role for millions of users seeking a more private and ad-free browsing experience, this study empirically investigates how the MV3 update affects their ability to block ads and trackers. Through a browser-based experiment conducted across multiple samples of ad-supported websites, we compare the MV3 to MV2 instances of four widely used ad blockers. Our results reveal no statistically significant reduction in ad-blocking or anti-tracking effectiveness for MV3 ad blockers compared to their MV2 counterparts, and in some cases, MV3 instances even exhibit slight improvements in blocking trackers. These findings are reassuring for users, indicating that the MV3 instances of popular ad blockers continue to provide effective protection against intrusive ads and privacy-infringing trackers. While some uncertainties remain, ad blocker providers appear to have successfully navigated the MV3 update, finding solutions that maintain the core functionality of their ad blockers.

翻译：谷歌近期对Chrome浏览器扩展的清单文件进行了更新——从清单版本2 (MV2)过渡到清单版本3 (MV3)——引发了用户和广告拦截器提供商的担忧。他们担心新的限制，特别是从功能强大的WebRequest API转向限制性更强的DeclarativeNetRequest API，可能会降低广告拦截器的有效性。鉴于广告拦截器对数百万寻求更私密、无广告浏览体验的用户至关重要，本研究通过实证方法调查了MV3更新如何影响其拦截广告和追踪器的能力。通过对多个广告支持网站样本进行基于浏览器的实验，我们比较了四款广泛使用的广告拦截器的MV3与MV2实例。结果显示，与MV2版本相比，MV3广告拦截器在广告拦截或反追踪有效性方面并未出现统计学意义上的显著下降，并且在某些情况下，MV3实例甚至在拦截追踪器方面表现出轻微改进。这些发现对用户而言是令人安心的，表明流行广告拦截器的MV3版本仍能有效抵御侵入性广告和侵犯隐私的追踪器。尽管仍存在一些不确定性，但广告拦截器提供商似乎已成功应对MV3更新，找到了维持其广告拦截器核心功能的解决方案。