Privacy Policy

Last updated: January 14, 2026

Overview

This Privacy Policy explains how the browser extension KanFan (看翻) (“the Extension”, “we”, “our”) handles user data.

We respect your privacy. The Extension is designed with a privacy-first and minimal-data principle. It only collects and processes the minimum data required to provide its core functionality: manga image translation, local performance optimization, and optional cloud-based translation reuse.

Information We Collect

The Extension may access, collect, or store the following types of data only when you actively use its features:

1. Anonymous User Identifier (UUID)

The Extension generates a random, anonymous unique identifier (UUID).

• Stored locally in your browser
  
  

• Used only to:
  
  

  • Prevent duplicate feedback submissions
    
    

  • Associate translation feedback (👍 / 👎) with the same anonymous user
    
    

We do not collect or store your name, email address, phone number, account credentials, or any personally identifiable information.

2. Page Information

When you request a translation, the Extension may access:

• The current page URL (with tracking parameters removed when possible)
  
  

• The page title
  
  

This information is used only to:

• Match existing cloud translation results
  
  

• Avoid duplicate processing of the same content
  
  

3. Image Data

The Extension processes image data strictly under user control.

• Only visible images or canvases selected or detected for translation are processed
  
  

• Image capture occurs only after user action or enabled auto-translate settings
  
  

• Images are sent securely to a backend service for OCR and translation
  
  

• Images are not recorded, monitored, or captured silently
  
  

4. Local Cache & IndexedDB Storage

To improve performance and reduce repeated network requests, the Extension uses IndexedDB and local storage to cache translation results.

• Cached data may include:
  
  

  • Image hash values
    
    

  • Translation results returned by the backend
    
    

• All cached data is stored locally on your device only
  
  

• IndexedDB data is never shared, sold, or transmitted to third parties
  
  

You may clear all cached data at any time using the Extension’s Clear function or by removing the Extension.

5. Language & Preference Settings

The Extension stores user preferences locally, including:

• Target translation language
  
  

• UI language
  
  

• Auto-translation and display preferences
  
  

These settings are stored using Chrome’s local storage and remain entirely on your device.

Network Request Handling

Declarative Network Request Permissions

The Extension uses Chrome’s declarativeNetRequest and declarativeNetRequestWithHostAccess APIs only to ensure images load correctly for translation.

Specifically:

• Temporary request header modifications (such as Referer) may be applied
  
  

• Rules are applied dynamically and temporarily
  
  

• No tracking, logging, or monitoring of your browsing activity occurs
  
  

• Network rules are not used for advertising, fingerprinting, or analytics
  
  

How We Use the Information

We use collected data only to:

• Perform OCR and translation
  
  

• Display translated text overlays
  
  

• Improve performance through local caching
  
  

• Enable optional cloud translation reuse
  
  

• Improve translation quality via anonymous feedback
  
  

We do not:

• Use data for advertising
  
  

• Track users across websites
  
  

• Sell, rent, or share data with third parties
  
  

Data Sharing & Third Parties

• Data is transmitted only to a secure backend service (AWS Lambda) for translation processing
  
  

• No data is shared with advertisers, analytics services, or data brokers
  
  

Data Retention

• Local data (IndexedDB, settings, UUID) remains until you clear it or uninstall the Extension
  
  

• Cloud-stored translation results may be retained to improve shared translation efficiency
  
  

• No personally identifiable data is stored in the cloud
  
  

Data Security

We apply reasonable technical safeguards, including:

• HTTPS-only communication
  
  

• Minimal data transmission
  
  

• No collection of sensitive personal information
  
  

Children’s Privacy

The Extension is not intended for children under the age of 13 and does not knowingly collect personal information from children.

Your Choices

You may:

• Disable automatic translation features
  
  

• Clear all cached translations and overlays
  
  

• Uninstall the Extension at any time to remove all local data
  
  

Changes to This Policy

We may update this Privacy Policy from time to time. Any changes will be reflected by updating the “Last updated” date above.

Contact

If you have any questions or concerns about this Privacy Policy, please contact:

Email: zshang2028@gmail.com