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Beta tool 2026

Web Firewall

Privacy-first Chrome extension for safer browsing — hides low-quality content, detects scam/dark pattern UI, and warns about prompt injection attacks targeting AI agents. Runs entirely locally.

Chrome ExtensionManifest V3JavaScriptContent Scripts

01 Details

About the Project

Web Firewall is a Chrome extension (Manifest V3) that provides three layers of protection while browsing. Everything runs locally — no page content is ever sent to external servers.

Problem

Modern websites are full of hidden manipulative elements: fake download buttons, aggressive overlay ads, dark patterns, and even prompt injection attacks targeting AI agents and scrapers. Regular users can't see these threats.

3 Protection Layers

  • Quality Shield (Noise Canceling) — automatically identifies and hides low-value content blocks: "related articles", aggressive CTAs, boilerplate. Preserves main content and navigation.
  • Scam Shield — detects fake download buttons, dark pattern overlays, interstitials, and clickfix patterns (PowerShell/terminal bait). Optional click-guard for high-risk elements.
  • Injection Shield — detects hidden text targeting AI agents/scrapers, prompt injection phrases, "agent bait" (requests for tokens, keys, clipboard access), and suspicious content in aria-label/alt/title/meta attributes.

Modes

  • Off — extension disabled for this site
  • Clean — light filtering, preserves most content
  • Focus — moderate filtering, hides sidebars and distractions
  • Strict — aggressive filtering, click-guards on risky elements

Design Principles

  • Local-first — all analysis runs in content scripts, no server calls (Free mode)
  • Safe by design — minimal permissions, no eval, no remote code
  • Fast — non-blocking, incremental analysis with debounced observers (< 150ms CPU)
  • Reversible — user can restore any hidden content
  • Explainable — all decisions include reasons and scores

The extension is in beta stage, preparing for Chrome Web Store release.

02 Screenshots