FlixPlus - Netflix Quality Enhancer

A Chrome extension that unlocks maximum video quality, HDR, and advanced audio features on Netflix.

Features

Video Quality

• Maximum Bitrate: Force highest available video and audio bitrate
• Force UHD/4K: Enable 4K playback on any screen resolution (requires Widevine L1)
• HDR Support: Force HDR/Dolby Vision when available
• Codec Optimization: Automatic selection of best video codec (HEVC/VP9/AV1)

Audio Enhancements

• Enhanced Audio: Enable Dolby Digital Plus & HE-AAC 5.1
• All Audio Tracks: Show all available audio tracks and subtitles
• Subtitle Options: Choose between SUP and IMSC subtitle formats

Other Features

• Household Check Bypass: Disable Netflix household verification
• Real-time Status Overlay: View current video quality, bitrate, and codec information
• Debug Tools: Built-in player info and stream selector

Security Features

IMPORTANT: This extension is RESTRICTED to netflix.com only and includes multiple security layers to protect against the obfuscated playercore file.

Multi-Layer Security Protection:

1. Domain Restriction (netflix.com only)

   • ✅ Manifest-level permissions
   • ✅ Runtime verification in every script
   • ✅ Cannot run on any other website

2. Network Request Monitoring

   • ✅ Whitelist-based filtering (only Netflix domains allowed)
   • ✅ Monitors fetch(), XMLHttpRequest, WebSocket
   • ✅ Blocks unauthorized external requests
   • ✅ Logs suspicious activity

3. File Integrity Verification

   • ✅ SHA-256 hash verification of cadmium-playercore.js
   • ✅ Alerts if file has been modified
   • ✅ Continuous integrity monitoring
   • ✅ Displayed in extension popup

4. Content Security Policy

   • ✅ No inline scripts allowed
   • ✅ No eval() of remote code
   • ✅ Only extension files can execute

5. Code Injection Prevention

   • ✅ Monitors eval() usage
   • ✅ Tracks Function() constructor
   • ✅ Detects suspicious code patterns

6. Data Protection

   • ✅ LocalStorage access monitoring
   • ✅ Cookie modification tracking
   • ✅ IFrame creation blocking
   • ✅ Prevents data exfiltration

Security Status Display:

Check the extension popup to see real-time security status:

• Network Protection: Active/Blocked requests
• File Integrity: Verified/Failed
• Suspicious Activity: Count of blocked attempts

See SECURITY.md for complete security documentation.

Installation

Method 1: Load Unpacked Extension (Development)

1. Open Chrome Extensions page:

   • Navigate to chrome://extensions/
   • Or click Menu (⋮) → Extensions → Manage Extensions

2. Enable Developer Mode:

   • Toggle the "Developer mode" switch in the top-right corner

3. Load the extension:

   • Click "Load unpacked"
   • Navigate to /Users/devin/Projects/FlixPlus/extension
   • Click "Select"

4. Verify installation:

   • You should see "FlixPlus - Netflix Quality Enhancer" in your extensions list
   • The extension icon should appear in your Chrome toolbar

Method 2: Package as CRX (Recommended for Personal Use)

1. Package the extension:

   cd /Users/devin/Projects/FlixPlus
   # Chrome will create a .crx file

   • Go to chrome://extensions/
   • Click "Pack extension"
   • Extension root directory: Select the extension folder
   • Click "Pack Extension"

2. Install the packaged extension:

   • Drag and drop the .crx file to chrome://extensions/

Usage

Basic Usage

1. Install the extension (see above)
2. Navigate to Netflix: Go to https://www.netflix.com
3. Extension auto-activates: FlixPlus starts working automatically
4. Configure settings: Click the FlixPlus icon in Chrome toolbar

Settings Configuration

Click the FlixPlus extension icon to access settings:

Video Quality Settings

• ✅ Maximum Bitrate (Recommended: ON) - Forces highest available quality
• ✅ Force UHD/4K (Use if you have 4K content) - Enables 4K on any screen
• ⬜ Always Use HDR (Use if you have HDR display) - Forces HDR/DV playback

Audio Settings

• ✅ Enhanced Audio (Recommended: ON) - Enables DD+/Atmos
• ✅ All Audio Tracks (Recommended: ON) - Shows all available audio options

Other Features

• ✅ SUP Subtitles (Recommended: ON) - Better subtitle format
• ✅ Disable Household Check (Optional) - Bypass household verification

Viewing Quality Information

Press Ctrl+Alt+Shift+F while watching Netflix to toggle the status overlay.

The overlay shows:

• Current video resolution (e.g., 3840x2160 4K UHD)
• Video bitrate (e.g., 15-25 Mbps)
• Video codec (HEVC/VP9/AV1/H.264)
• Audio bitrate and codec
• DRM system in use (Widevine/PlayReady)
• HDR status

Debug Tools

From the extension popup:

• Show Player Info: Opens Netflix's built-in player debug info (Ctrl+Alt+Shift+D)
• Stream Selector: Opens Netflix's stream quality selector (Ctrl+Alt+Shift+B)

How It Works

Netflix Plus Core

• Intercepts Netflix's playercore loading
• Replaces with modified version that unlocks quality restrictions
• Spoofs browser capabilities to enable higher quality streams
• Forces best available video and audio bitrate selection

Netflix UHD

• Spoofs screen resolution to 8K (7680x4320)
• Hooks into DRM systems (Widevine/PlayReady)
• Reports all video formats as smooth and power-efficient
• Bypasses hardware limitation checks

Status Overlay

• Monitors video element properties in real-time
• Accesses Netflix's internal player API when available
• Provides visual feedback on quality improvements

Verifying It's Working

Method 1: Use the Status Overlay

1. Start playing any Netflix video
2. Press Ctrl+Alt+Shift+F to show the overlay
3. Check the resolution - should show 1080p or higher
4. Check bitrate - should show higher values (8-25 Mbps for HD/4K)

Method 2: Use Netflix Debug Info

1. While playing, press Ctrl+Alt+Shift+Shift+D (or click "Show Player Info" in extension)
2. Look for:
   • Playing bitrate (should be highest available)
   • Resolution (1920x1080 or 3840x2160)
   • Audio codec (should show DD+ or Atmos if available)

Method 3: Visual Inspection

• Video should look noticeably sharper
• Check for HDR badge on compatible content
• Audio should sound richer with surround sound content

Troubleshooting

Extension not working?

1. Refresh Netflix page after installing
2. Check you're on Netflix: Extension only works on netflix.com
3. Clear browser cache: Settings → Privacy → Clear browsing data
4. Reload extension: chrome://extensions/ → Click reload icon

Still seeing low quality?

1. Check your Netflix plan: 4K requires Premium plan
2. Check your internet speed: Need 25+ Mbps for 4K
3. Verify Widevine L1: Some PCs don't support hardware DRM for 4K
4. Try different content: Not all titles available in 4K/HDR

Playback issues?

1. Disable some features: Try turning off "Force UHD" if having buffering
2. Check console: Open DevTools (F12) and look for FlixPlus logs
3. Reset settings: Turn all settings off, then enable one at a time

Requirements

Minimum Requirements

• Google Chrome 88+ or Chromium-based browser
• Netflix account (any plan works, but Premium for 4K)
• Stable internet connection (5+ Mbps)

Recommended for Best Results

• Netflix Premium plan (for 4K content)
• 25+ Mbps internet connection
• Display that supports 1080p or higher
• Widevine L1 DRM support (for 4K)
• HDR-capable display (for HDR/Dolby Vision)

Limitations

• 4K playback: Requires Widevine L1 hardware DRM (not available on all systems)
• Content availability: Quality depends on what Netflix offers for each title
• Network speed: Higher quality requires faster internet
• Browser limitations: Some features may not work on all Chromium browsers

Important Notes

⚠️ Terms of Service: Using this extension may violate Netflix's Terms of Service. Use at your own risk.

⚠️ Personal Use Only: This extension is for personal use only. Do not redistribute or commercialize.

⚠️ No Guarantees: Video quality depends on many factors including your plan, internet speed, and device capabilities.

✅ Privacy: This extension does not collect, transmit, or store any personal data. All settings are stored locally in Chrome.

✅ Open Source: All code is available for review. No obfuscation or hidden functionality (except the modified Netflix playercore which is pre-obfuscated by Netflix).

Credits

Based on userscripts:

• Netflix Plus by TGSAN
• Netflix UHD by TGSAN

Modified and packaged as a Chrome extension with:

• Modern UI
• Enhanced security (netflix.com restriction)
• Local file loading (no external dependencies)
• Real-time quality monitoring

License

For educational and personal use only. Not affiliated with or endorsed by Netflix.

Changelog

v1.0.0 (Initial Release)

• Combined Netflix Plus and Netflix UHD functionality
• Modern popup UI with toggle switches
• Real-time status overlay
• Restricted to netflix.com only
• Local playercore loading (no external requests)
• Chrome storage for settings
• Debug tools integration