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Preview of Privacy Shield

Privacy Shield by Arthur

See what websites know about you. Detects fingerprinting, trackers, and manipulative UI tricks. Works offline, no data leaves your browser

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About this extension
Browser extension that shows you what websites know about you. Detects fingerprinting, trackers, and dark patterns. 100% offline and private.

Fingerprint Detection 🔍

Detects 19+ fingerprinting techniques:
- Canvas - Drawing patterns unique to your GPU
- WebGL - GPU renderer and vendor info
- Audio - AudioContext processing differences
- Fonts - List of installed fonts
- Screen - Resolution, color depth, pixel ratio
- Navigator - User agent, language, platform
- Hardware - CPU cores, device memory
- WebRTC - Local IP address leaks
- Timezone - Timezone offset fingerprinting
- Plugins - Installed browser plugins
- Battery - Battery status API
- Client Rects - Element rendering differences
- Speech - Available speech synthesis voices
- Storage Estimate - Available storage detection
- Media Devices - Connected media devices
- Permissions - Granted permissions fingerprinting
- CSS Media - Media query fingerprinting
- Gamepad - Connected gamepads

Tracker Detection 📊

Identifies known trackers:
- Google Analytics, Facebook Pixel, TikTok, etc.
- Ad networks (Criteo, Taboola, DoubleClick)
- Analytics services (Hotjar, Mixpanel, Segment)
- Session replay tools
- Social media widgets
- Tracking cookies & URL parameters
- Bounce trackers & beacon trackers

API Monitoring

Alerts when pages access:
- Geolocation
- Camera / Microphone
- Clipboard (read/write)
- Notifications
- Local storage usage

Dark Patterns (16 categories)

Detects manipulative UI patterns:
- Confirmshaming - Guilt-trip decline buttons
- Visual Misdirection - Hidden/tiny reject buttons
- Fake Urgency - Countdown timers, "only X left"
- Pre-selection - Pre-checked marketing consent
- Hidden Cost - Surprise fees at checkout
- Cookie Banner Manipulation - Deceptive cookie dialogs
- Obstruction - Hard to cancel/unsubscribe
- Sneaking - Adding items to cart without consent
- Trick Questions - Confusing double-negatives
- Disguised Ads - Ads that look like content
- Forced Continuity - Hard to cancel subscriptions
- Nagging - Repeated popups and interruptions
- Privacy Zuckering - Confusing privacy settings
- Social Proof - Fake reviews/activity notifications
- Roach Motel - Easy to sign up, hard to leave
- Notification Spam - Excessive push notification requests

Privacy Score
Each page gets a privacy score (0-100) and grade (A-F) based on:
- Fingerprinting techniques detected
- Number of trackers
- Tracking cookies
- Sensitive API access
- Dark patterns found

Settings
- Toggle individual detection modules
- Sensitivity levels (low/medium/high)
- Auto-scan on page load
- Show badge count on icon
- Notify on high-risk sites
- Highlight detected elements on page
- Whitelist trusted domains

Statistics
- Total scans performed
- Average privacy score
- Total trackers/patterns detected
- Worst and best sites list

Privacy

100% Offline & Private:
- All detection happens in your browser
- No data sent to external servers
- No tracking, no analytics
- No account required
- Settings stored locally only
- Open source
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Permissions and data

Required permissions:

  • Display notifications to you
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
  • Homepage
  • Support site
  • Support Email
Version
1.0.0
Size
123.6 KB
Last updated
4 days ago (Jan 10, 2026)
Related Categories
  • Privacy & Security
License
Mozilla Public License 2.0
Privacy Policy
Read the privacy policy for this add-on
Version History
  • See all versions
Tags
  • privacy
  • security
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