Kristina Nikolic Egor Zverev Javier Rando Matthew Jagielski Edoardo Debenedetti Florian Tramèr Untrusted Content Masking for Web Agents with Security Guarantees. 2026 July abs/2607.05277 CoRR https://doi.org/10.48550/arXiv.2607.05277 db/journals/corr/corr2607.html#abs-2607-05277 streams/journals/corr