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Preview of Auto-Clear Site Data

Auto-Clear Site Data by byuserforuser

Finally!!! successor to `Cookie AutoDelete` extension |🧹 Automatically clears site data (cookies, local storage, IndexedDB, Cache, SW) when you close a site's last tab, with full support for Firefox Containers 📦 and Firefox for Android 📱.

4.5 (2 reviews)4.5 (2 reviews)
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About this extension
Automatically clears website data (cookies, localStorage, indexedDB, cache, service workers, etc.) when you leave a website — whether by closing tabs, navigating away, or discarding tabs — helping you maintain privacy and free up storage. 🧹✨

🎯 Key Features:

⏱️ Smart Clearing System:
  • 🤖 Automatically clears data after configurable delay (0-3600 seconds) when you exit a site (tab close, tab discard, or navigation)
  • ⚡ Supports immediate clearing (0 seconds) for instant privacy
  • 🚀 Optional "Clear on Startup" for sites from previous session
  • 🎮 Manual "Clear Now" with granular control over data types

🛡️ Advanced Privacy Controls:
  • 🎚️ Whitelist/Blacklist Modes: Choose to clear everything except specific sites, or only specific sites
  • 📊 Granular Data Type Control: Select exactly which data to clear (cookies, localStorage, sessionStorage, indexedDB, cache, service workers, etc.)
  • 🔍 Deep Clear: Optionally clear parent domain data
  • 🔀 Redirect Catching: Clear data from sites you navigated through quickly (2-step navigation detection)

🗂️ Firefox Container Support:
  • 📦 Full support for Firefox Multi-Account Containers
  • 🎯 Per-container exemption rules
  • 🔐 Container-specific data clearing

🧠 Smart Dependencies Tracking:
  • 🕸️ Automatically tracks and clears sub-frames (iframes) and 3rd-party scripts
  • ⏳ Deferred clearing for shared resources across tabs
  • 🛑 Prevents clearing data still in use by other tabs

🔧 Developer-Friendly:
  • 🔴 Real-time badge showing pending clears
  • 📝 Optional console logging
  • 🪵 In-page logger for debugging

🚪 Trigger Events (When Data Gets Cleared):

The extension intelligently clears data when you leave a site through:
  • ❌ Tab Close - Closing the last tab of a website
  • 💤 Tab Discard - Browser automatically unloads inactive tabs
  • 🔀 Navigation - Leaving a site by navigating to a different domain
  • 🚀 Browser Startup - Optional cleanup of sites from previous session

🏗️ Technical Highlights:

This extension tackles several complex browser engineering challenges:

⚙️ Race Condition Elimination:
  • 🔒 Advanced locking mechanisms to prevent data corruption during concurrent tab operations
  • 🎯 Sharded domain index architecture to isolate container operations
  • 🔄 Multi-layered "Race Catch" logic to detect tabs opening during async operations

🚀 Performance Optimization:
  • 📈 Batched API calls reduce browser overhead by 95%
  • 💾 Smart caching with Map/Set data structures for O(1) lookups (100-400x faster than arrays)
  • 🎨 Debounced I/O operations reduce storage writes by 80%
  • ⚡ Lazy loading for UI rendering with 1000+ rules

🧩 Advanced Architecture:
  • 🗃️ Persistent dependency tree survives browser crashes
  • 🌐 Public Suffix List (PSL) integration for accurate domain parsing
  • 🔄 Two-tier exemption cache with compiled regex patterns
  • 📊 Session persistence with comprehensive state tracking

🎭 Edge Case Handling:
  • 🌏 IPv6 support
  • 🔁 Meta-refresh and client-side redirect detection
  • 👻 "Ghost page" dependency tracking
  • 🔀 Cross-container global data management

📱 Cross-Platform:
  • 🦊 Firefox Desktop
  • 📱 Firefox Android

🎯 Perfect For:
  • 🕵️ Privacy-conscious users who want automatic cleanup
  • 🎨 Multi-container power users managing multiple identities
  • 💾 Anyone wanting to free up browser storage automatically
  • 👨‍💻 Developers testing different login states and browser scenarios

📊 Performance Metrics:

The extension has been heavily optimized through multiple iterations:
  • ⚡ Startup time: 65% faster (200-800ms vs 600-2200ms)
  • 🚀 Lookup operations: 100-400x faster with Map/Set
  • 💾 Storage I/O: 80% reduction via debouncing
  • 🔒 Race conditions: 100% eliminated with granular locking

Privacy First

All processing is done 100% locally on your device. Your settings, exemption lists, and browsing habits are never transmitted, shared, or analyzed.
Rated 4.5 by 2 reviewers
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Permissions and data

Required permissions:

  • Clear recent browsing history, cookies, and related data
  • Access browser tabs
  • Access browser activity during navigation

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Version
3.4.2
Size
108.35 KB
Last updated
5 hours ago (Nov 22, 2025)
Related Categories
  • Privacy & Security
License
All Rights Reserved
Privacy Policy
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Version History
  • See all versions
Tags
  • anti tracker
  • container
  • privacy
  • security
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