Webextensions can improve web browser privacy, security, and user experience. The APIs offered by the browser to webextensions affect possible functionality. Currently, Chrome transitions to a modified set of APIs called Manifest v3. This paper studies the challenges and opportunities of Manifest v3 with an in-depth structured qualitative research. Even though some projects observed positive effects, a majority expresses concerns over limited benefits to users, removal of crucial APIs, or the need to find workarounds. Our findings indicate that the transition affects different types of webextensions differently; some can migrate without losing functionality, while other projects remove functionality or decline to update. The respondents identified several critical missing APIs, including reliable APIs to inject content scripts, APIs for storing confidential content, and others.

翻译：Web扩展能够提升网络浏览器的隐私性、安全性及用户体验。浏览器向Web扩展提供的API决定了其可实现的功能范围。当前，Chrome正转向采用一套名为Manifest v3的改良API集。本文通过深入的定性结构化研究，探讨Manifest v3带来的挑战与机遇。尽管部分项目观察到了积极影响，但大多数受访者表达了对用户获益有限、关键API被移除或需寻找替代方案的担忧。我们的研究结果表明，此次转型对不同类型的Web扩展影响各异：部分扩展可在不损失功能的情况下完成迁移，而其他项目则选择削减功能或拒绝更新。受访者指出了若干关键缺失的API，包括可靠的内容脚本注入API、机密内容存储API等。