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LibreJS reaches version 5.4

by wtheaker Contributions Published on Oct 23, 2013 02:22 PM
GNU LibreJS is a Web browser extension that protects users by identifying proprietary JavaScript and encourages people to write to Webmasters about free JavaScript.
LibreJS - Free JavaScript in your browser

Our campaign to promote free JavaScript for the Web is still ongoing, and LibreJS is an instrumental tool for allowing people who aren't licensing experts to participate. This plugin reveals just how much of the Web depends on proprietary JavaScript and how little works without it. New users will see that many popular Web sites break and get a sense of the amount of proprietary software that is imposed upon users without their knowledge. Installing LibreJS is an important step towards protecting users from nonfree JavaScript.

JavaScript presents a danger to Web users because, in almost all cases, Web applications written in JavaScript are executed silently by browsers without informing users. LibreJS empowers users to choose to only allow free JavaScript—code that does not impinge on their essential freedoms—, and this new release introduces some big features.

The major improvements include:

  • Support for magnet links.
    The new scheme using magnet links is now implemented, which means that magnet links can be used for JavaScript License Web Label pages. JavaScript Web Labels are a method for specifying free software licenses, particularly for complying with ones that require including the license document, in minified JavaScript code. Magnet links will make it much easier for Webmasters to cleanly code sites that are LibreJS compliant.

  • Scripts are analyzed individually.
    Labels can be appended to a single script, whether it is inline (on the page) or as a separate external script. This new format allows some inline scripts to be enabled as free while nonfree scripts remain blocked.

  • Scripts are evaluated with a hash.
    Now JavaScript Web Labels don't require a full path to the JavaScript to accept it, and instead a SHA-1 hash is used to determine what script is labelled as free. In other words, it's the text of the script that is checked, rather than the URL.

  • Display info in the add-on panel.
    Information on why a script is blocked or accepted is displayed to the user from the add-on panel. For instance, a script detected as free will have a line giving the name of the script. A script that is blocked will have meaningful information why it has been blocked.

You can download the extension to see the complete changelog. LibreJS is licensed under the GPL and is available for Icecat or any other Mozilla-based browsers. When you install LibreJS, you protect yourself from the dangers of proprietary JavaScript and can help join the fight for a free Web.

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