Mozilla Firefox is a free, open-source and cross-platform web browser for Windows, Linux, MacOS X and many other operating systems. It is fast and easy to use, and offers many advantages over other web browsers, such as tabbed browsing and the ability to block pop-up windows. Firefox also offers excellent bookmark and history management, and it can be extended by developers using industry standards such as XML, CSS, JavaScript, C++, etc. Many extensions are available. Note: Due to upstream's trademark policies, this package identifies as "Nightly" rather than "Firefox" by default.