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James Clarke, Maryam Mehrnezhad, Ehsan Toreini (2026), In: ACM transactions on privacy and security ACM

Browser extensions are commonly used to improve the browsing experience and accessibility. However, installing extensions naturally increases the user’s risk. This work presents AXECC, a novel framework for measuring the impact of web tracking and accessibility. The AXECC framework includes static, dynamic, and accessibility analyses across multiple web pages. We utilise the AXECC framework to analyse the web tracking and accessibility impact in the wild on 21k real-world extensions collected from the Chrome Web Store. In our analysis, we identify that 15.97% of extensions (with more than 600M users) perform a type of third–party tracking in the first 60 seconds after loading. These results are highly correlated with the extension category and are consistent across different web pages. Furthermore, we find that a small number of extensions (with 65M users) alter the accessibility of a web page when browsing, and these alterations are often complex and involve more tracking. Our work reveals a significant privacy risk from web tracking within popular browser extensions, often intertwined with complex accessibility alterations.

James M. Clarke, Maryam Mehrnezhad, Ehsan Toreini (2024), In: ACM transactions on accessible computing17(1)1pp. 1-39 ACM

This article investigates the accessibility of cookie notices on websites for users with visual impairments (VI) via a set of system studies on top UK websites (n=46) and a user study (n=100). We use a set of methods and tools—including accessibility testing tools, text-only browsers, and screen readers—to perform our system studies. Our results demonstrate that the majority of cookie notices on these websites have some form of accessibility issue, including contrast issues, not having headings, and not being read aloud immediately when the page is loaded. We discuss how such practices impact the user experience and privacy and provide a set of recommendations for multiple stakeholders for more accessible websites and better privacy practices for users with VIs. To complement our technical contribution, we conduct a user study, finding that people with VIs generally have a negative view of cookie notices and believe our recommendations could help their online experience.