gorhill/uBlock
UBlock
uBlock is a browser-based content blocker that functions as a declarative filtering engine to intercept network requests and modify web page content. It operates by parsing standardized filter lists into optimized data structures, allowing it to block network hosts, enforce security policies, and prevent unauthorized data transmission. The extension provides a comprehensive security layer that monitors outgoing traffic and disables intrusive browser features to enhance user privacy.
What distinguishes this project is its granular control over filtering behavior through a dynamic rule orchestrator. Users can manage custom rules, apply site-specific overrides, and toggle filtering settings on a per-domain basis. The engine also employs advanced techniques such as CNAME uncloaking, IP address filtering, and response body modification to identify and neutralize trackers that attempt to bypass standard blocking methods. Furthermore, it supports enterprise-grade deployment, enabling organizations to enforce consistent security and filtering configurations across managed environments.
The project covers a broad capability surface including cosmetic page modification, which uses CSS injection and sandboxed scriptlets to remove visual clutter and neutralize anti-blocking scripts. It also provides interactive tools for real-time network traffic inspection and manual element removal, ensuring users can debug and customize their browsing experience. The extension is designed to maintain high performance by synchronizing its initialization at startup, ensuring that all security rules are active before any network requests are processed.
Features
- Network Host Blockers - Blocks network requests to specific hostnames and subdomains by applying declarative filter lists.
- Declarative Filtering Engines - Interprets standardized, rule-based filter lists to determine how network traffic and page elements are handled.
- Enterprise Browser Management - Maintains consistent security and filtering configurations across organizational environments to ensure safe browsing.
- Resource Restriction Policies - Enforces security policies that restrict unauthorized resource loading and mitigate potential data leakage.
- Browser Privacy Configurations - Prevents unintended network connections by disabling browser-level features like resource prefetching and hyperlink auditing.
- Response Body Modifiers - Strips unwanted content from HTTP response bodies before the browser renders the page.
- Blocking Mode Configurations - Adjusts filtering intensity to balance site compatibility with strict security requirements.
- Browser-Based Content Blockers - Intercepts browser network requests to filter out advertisements, trackers, and unwanted resources.
- Cosmetic Filtering Engines - Modifies page layouts by injecting CSS selectors that hide unwanted visual elements.
- Dynamic Filter Targeting - Targets specific content for blocking using hostname patterns and regular expressions.
- External Filter List Integrations - Imports and parses third-party rule sets to manage network or DOM-based blocking across various environments.
- Privacy Hardening Tools - Hardens browser privacy by disabling tracking mechanisms and intrusive features.
- Dynamic Rule Orchestrators - Coordinates real-time blocking behavior through site-specific overrides and custom rule management.
- Content Filtering Engines - Improves page performance and privacy by intercepting and blocking unwanted web elements and network requests.
- Declarative Filter Compilers - Transforms human-readable filter lists into optimized data structures for high-performance matching.
- Network Interceptors - Filters outgoing browser traffic to prevent unauthorized data transmission and protect user privacy.
- Site Filtering Toggles - Offers a dashboard interface to toggle filtering rules instantly for the currently active website.
- Per-site Configuration Settings - Customizes extension behavior on a per-domain or per-website basis.
- Network Traffic Inspectors - Analyzes browser network requests and resource loading in real-time.
- Cosmetic Page Modifiers - Injects custom CSS and scripts to hide or remove specific visual elements from rendered web pages.
- Adblocker Compatibility - Core engine for content filtering and cosmetic rule application.
- Browser Extensions - Efficient ad and content blocking for web browsers.
- Redirection And Utilities - Efficient browser extension for blocking advertisements and trackers.
- Ad Blocking Tools - Efficient browser extension for blocking ads and malicious content.
- Content Blockers - Industry-standard browser extension for efficient ad and content filtering.
- Privacy and Encryption - Efficient wide-spectrum content blocker for browsers.
- Security And Privacy - Efficient content blocker for web browsers.
- CNAME Uncloaking Tools - Resolves CNAME records to expose and block third-party trackers masking as first-party connections.
- HTML Content Filters - Purges specific HTML elements from documents during the initial page load process.
- Interactive Element Removers - Enables manual selection of DOM elements to hide specific page components from view.
- Traffic Interception Tools - Directs network traffic flow by blocking requests to domains associated with tracking or malicious activity.
- Security Header Injections - Appends security-focused HTTP headers to responses to restrict unauthorized resource loading.
- IP Address Filters - Blocks network connections by matching destination IP addresses against established blocklists.
- Startup Synchronization - Pauses network activity during browser startup until all security rules are fully loaded and active.
Star history
How this analysis was created: This summary and feature list are AI-generated from collected project material and can contain mistakes. Stars, license and language are imported from GitHub. Inclusion does not mean that we have tested or audited this project. Check the source documentation for any feature you depend on. Learn more on our About page.
