New features and improvements:

A descriptive label can be assigned to a whitelist entry.
Whitelist URL entry is more flexible: it supports IPv4, IPv6, domain, multiple protocols, port and so on.
Removed the http(s) protocol limitation.
A welcome page is shown when the extension is installed.
Added two icon that represent the extension status.
When the extension blocks/redirects an URL an info page is displayed.
Added the block only policy. It's the default one.
Through the toolbar button the user can open settings rapidly.
Through the toolbar button the user can whitelist specific resource, currently blocked in the active tab.
Chrome/ium package. So programmatically installation is supported.
Firefox installation improved.
Whitelist entry modification is now really simple.
Improved whitelist table. Each row describes the entries better.
Improved UX and UI.
Improved HTML and CSS.
Code was written from scratch. It's simpler, more flexible and better structured.
Code is based on immutable objects.
Message-based architecture.
Improved the whitelist entry format. It's more flexible.
Improved directory structure.
Removed incompatible stuffs with Qubes 4.0.
The extension prints on the console blocked/permitted URL.

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