IceCat

and GNU IceCat is the GNU version of the Firefox browser. Its main advantage is an ethical one: it is entirely free software. While the Firefox source code from the Mozilla project is free software, they distribute and recommend nonfree software as plug-ins and addons. Also their trademark license imposes requirements for the distribution of modified versions that make it inconvenient to exercise freedom 3. Privacy protection features LibreJS: GNU LibreJS aims to address the JavaScript problem described in Richard Stallman's article The JavaScript Trap. JShelter: Mitigates potential threats from JavaScript, including fingerprinting, tracking, and data collection. Slightly modifies the results of API calls, differently on different domains, so that the cross-site fingerprint is not stable. Applies security counter-measures that are likely not to break web pages. Allows fine-grained control over the restrictions and counter-measures applied to each domain. Fingerprinting countermeasures: Fingerprinting is a series of techniques allowing to uniquely identify a browser based on specific characterisics of that particular instance (like what fonts are available in that machine). Unlike cookies, the user cannot opt-out of being tracked this way; so the browser has to avoid giving away these kinds of hints.