擴充套件就像是在瀏覽器中安裝外掛。
它們為 Firefox 新增功能，讓上網變得更快、更聰明，或更好玩。
Privacy Possum
Privacy Possum monkey wrenches common commercial tracking methods by reducing and falsifying the data gathered by tracking companies.
113,728 位使用者
SoundFixer
Helps you fix annoying sound problems on sites like YouTube: audio in one channel only, too quiet or too loud. (Unfortunately, this extension does not work on all websites because of cross-domain issues — but it does work on YouTube!)
21,314 位使用者
Decentraleyes
保護您不受「免費」、中心化的內容傳遞網路（CDN）的追蹤。此附加元件可防止您的瀏覽器送出請求到 Google Hosted Libraries 這類的服務，並在本機提供程式庫以達到相同的效果，而不造成網頁錯誤。可補充一般內容封鎖器的功能。
254,501 位使用者
Facebook Container
Prevent Facebook from tracking you around the web. The Facebook Container extension for Firefox helps you take control and isolate your web activity from Facebook.
1,009,989 位使用者
LastPass Password Manager
LastPass, an award-winning password manager, saves your passwords and gives you secure access from every computer and mobile device.
957,681 位使用者
1Password X – Password Manager
The best way to experience 1Password in your browser. Easily sign in to sites, generate passwords, and store secure information, including logins, credit cards, notes, and more.
76,942 位使用者
RoboForm Password Manager
RoboForm, the #1 ranked Password Manager makes your life easier by remembering passwords and logging you into websites automatically
90,474 位使用者