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Preview of BlockLang

BlockLang by MadJi

Browser extension that filters Google and Bing search results by blocking unwanted websites and languages. Features built-in Russian domain filter (89+ sites) plus fully customizable filtering - add your own sites, domains, and languages to block.

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Extension Metadata

About this extension
BlockLang – Extension Overview

BlockLang is a lightweight and privacy-friendly browser extension designed to help users filter out unwanted search results, especially those in Russian, when using Google or Bing.
You can also add your own filters for any domain or language you wish to block.

Also available for:
- Chrome: https://chromewebstore.google.com/detail/search-language-filter/jhaaififdgohacmbigmellnhiihiidee
- Safari: Available on iOS App Store

Why This Extension Was Created

The extension was initially developed to address a real-world issue experienced by Bulgarian users:
Even when searching in Bulgarian, search engines often return results from Russian-language websites — which are irrelevant, unhelpful, or even misleading.
The goal was to create a tool that automatically appends language and domain filters to search queries, making the search experience cleaner, more relevant, and more local.

What It Does
  • Automatically adds advanced search filters like -lang:ru or -site:*.ru to your search queries on Google and Bing
  • Hides search results from predefined Russian domains or languages
  • Toggle filtering ON/OFF at any time via a simple popup interface
  • Custom blacklists - add unlimited domains you want to exclude (e.g., cnn.com, reddit.com, etc.)
  • Instant application - changes apply immediately, with no need to reload or restart the browser
  • Enhanced UI with improved user experience and new button views
  • Advanced toggle controls in settings menu for better customization

Features
  • Works seamlessly on Google and Bing
  • Simple ON/OFF toggle from the popup
  • Add unlimited filters (block any domain or language)
  • Remove filters easily with intuitive interface
  • Unlimited language blocking for comprehensive filtering
  • Unlimited domain filters - no restrictions or paid subscriptions
  • Privacy-focused: Runs only in your browser (no data is collected or sent anywhere)
  • Performance optimized for faster operation
  • Completely free - all features available at no cost

How to Use the Custom Blacklist

You can block any domain, subdomain, or language, but it's important to format them correctly.

How to Add Domains

When adding a domain, you do not need to type the full filter (like -site:). Just enter the domain name and the extension will automatically convert it into the correct filter format.

You type:

cnn.com


The extension converts it to:

-site:cnn.com


You can also block subdomains:

You type:

.example.org


The filter becomes:

-site:.example.org


Block specific Wikipedia sections:

You type:

.wikipedia.org/lang=ru


Resulting filter:

-site:.wikipedia.org/lang=ru


Examples

Example 1 – Basic usage

Search:

дума


Actual query sent by extension:

дума -lang:ru -site:.ru -site:.su -site:*.рф …


Example 2 – With custom filter added

You added: reddit.com

Query becomes:

your keywords -site:reddit.com …


Privacy

Your data stays local.
- No tracking
- No network requests
- No analytics
- No data collection or sharing
- Preferences are saved in your browser storage only
- All filtering happens locally on your device

Firefox Version Benefits
  • Completely free - no paid subscriptions or premium features
  • Unlimited filtering - add as many domain and language filters as you need
  • Full feature access - all functionality available without restrictions
  • No account required - works immediately after installation
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Permissions and dataLearn more

Required permissions:

  • Display notifications to you
  • Access browser tabs
  • Access your data for sites in the google.com domain
  • Access your data for sites in the bing.com domain

Optional permissions:

  • Access your data for all web sites
More information
Add-on Links
  • Homepage
  • Support site
  • Support Email
Version
1.5.0
Size
28.35 kB
Last updated
20 days ago (23 Jul 2025)
Related Categories
  • Search Tools
  • Language Support
  • Tabs
Licence
MIT Licence
Privacy Policy
Read the privacy policy for this add-on
End-User Licence Agreement
Read the licence agreement for this add-on
Version History
  • See all versions
Tags
  • content blocker
  • dark mode
  • google
  • privacy
  • search
  • translate
  • user scripts
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Release notes for 1.5.0
Version 1.5.0
• Added scam protection system with real-time domain checks
• Full-page warnings for dangerous or untrusted websites
• New setting to enable or disable scam protection
• Minor performance improvements and bug fixes
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