Ghostery is a free and open-source privacy and security-related browser extension and mobile browser application.

Firebug is a discontinued free and open-source web browser extension for Mozilla Firefox that facilitated the live debugging, editing, and monitoring of any website's CSS, HTML, DOM, XHR, and JavaScript.

At Mozilla, we’re a global community of technologists, thinkers and builders working together to keep the Internet alive and accessible, so people worldwide can be informed contributors and creators of the Web. We believe this act of human collaboration across an open platform is essential to individual growth and our collective future.

Adblock Plus, the most popular ad blocker on Firefox, Chrome, Safari, Android and iOS. Block pop-ups and annoying ads on websites like Facebook and YouTube.