Font Contrast is a free and open-source add-on for Firefox designed to improve the readability of text on websites suffering from poor design choices. It offers a range of features aimed at combating hard-to-read text, including the ability to turn text to black or a darker shade, enlarge small fonts, and increase font boldness. Users can easily toggle these settings on and off by clicking the icon or using the default keyboard shortcut, Shift+F1.

The add-on also includes an address bar button that allows for quick adjustments of website-specific options, enhancing user experience. Being lightweight and fast, it performs efficiently even on large websites, making it a practical tool for anyone seeking to improve text legibility while browsing. As free software, Font Contrast is released under the GNU General Public License v3.0, ensuring that users can benefit from its features without any cost.