uMatrix by Raymond Hill

uMatrix: A point-and-click matrix-based firewall, with many privacy-enhancing tools.

*For advanced users.*

uMatrix put you in full control of where your browser is allowed to connect, what type of data it is allowed to download, and what it is allowed to execute. Nobody else decides for you: You choose. You are in full control of your privacy.

Out of the box, uMatrix works in relax block-all/allow-exceptionally mode, meaning web sites which require 3rd-party scripts are likely to be "broken". With two clicks, uMatrix can be set to work in allow-all/block-exceptionally mode, which generally will not break web sites. See https://github.com/gorhill/httpswitchboard/wiki/How-to-use-HTTP-Switchboard:-Two-opposing-views for more details on this topic.

* See ALL the remote connections, failed or attempted, depending on whether they were blocked or allowed (you decide).

* A single-click to whitelist/blacklist one or multiple classes of requests according to the destination and type of data (a blocked request will NEVER leave your browser).

* Efficient blacklisting: cookies won't leave your browser, JavaScript won't execute, plugins won't play, tracking pixels won't download, etc.

* You do not have to solely rely on just one particular curated blacklist (arguably with many missing entries) outside which nothing else can be blocked: You are in full control.

* Ease of use: uMatrix lets you easily whitelist/blacklist net requests which originate from within a web page according to a point-and-click matrix:

- domain names (left column)
* from very specific
* to very generic

- type of requests (top row)
* cookies
* CSS-related resources (stylesheets and web fonts)
* images
* plugins
* scripts
* XHR (requests made by scripts)
* frames
* others

You can blacklist/whitelist a single cell, an entire row, a group of rows, an entire column, or the whole matrix with just one click.

uMatrix's filtering engine uses precedence logic to evaluate what is blocked/allowed according to which cells are blacklisted/whitelisted. For example, this allows you to whitelist a whole page with one click, without having to repeatedly whitelist whatever new data appear on the page.

All rules are scoped. For example, you can block `facebook.com` and `facebook.net` everywhere except when visiting a page on `www.facebook.com`. This way Facebook won't be able to build a profile of your browsing habits.

The goal of this extension is to make the allowing or blocking of web sites, wholly or partly, as straightforward as possible, so as to encourage users to care about their privacy.

The extension comes with 3rd-party hosts files totaling over 62,000 distinct hostnames (lists can be selectively disabled/enabled according to your choice).

Ultimately, you can choose however you browse the net:

* Blacklist all by default, and whitelist as needed (default mode).

* Whitelist all by default, and blacklist as needed.

Either way, you still benefit from the preset blacklists so that at least you get basic protection from trackers, malware sites, etc. Or you can disable all of these preset blacklists.

Your choice.

Randomly assembled documentation: https://github.com/gorhill/uMatrix/wiki

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This extension is also useful to understand what the web page in your browser is doing, often without your knowledge. You have full ability to see and decide with whom a web page communicates, and to restrict these communications to specific classes of objects within the web page.

The number which appear in the extension icon correspond to the total number of distinct requests attempted (successfully or not depending on whether these were allowed or blocked) by the web page.

Simply click on the appropriate entry in the matrix in order to white-, black- or graylist a component. Graylisting means the blocked or allowed status will be inherited from another cell with higher precedence in the matrix.

Red square = effectively blacklisted, i.e. requests are prevented from reaching their intended destination:
* Dark red square: the domain name and/or type of request is specifically blacklisted.
* Faded red square: the blacklist status is inherited because the entry is graylisted.

Green square = effectively whitelisted, i.e. requests are allowed to reach their intended destination:
* Dark green square: the domain name and/or type of request is specifically whitelisted.
* Faded green square: the whitelist status is inherited because the entry is graylisted.

The top-left cell in the matrix, the "all" cell, represents the default global setting, which allows you to choose whether allowing or blocking everything is the default behavior. Some prefer to allow everything while blocking exceptionally. My personal preference is of course the reverse, blocking everything and allowing exceptionally.

This extension is also useful if you wish to speed up your browsing, by globally blocking all requests for images as an example.

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BUGS, ISSUES: https://github.com/gorhill/uMatrix/issues

SOURCE CODE: https://github.com/gorhill/uMatrix (GPLv3)

CHANGE LOG: https://github.com/gorhill/uMatrix/releases