5. Adblock Plus – Adblock Plus helps users to see ad free websites, if you hate seeing ads, this Firefox add on will help you to browse ad free internet. This add on has many useful features that can help users to reduce site load time by blocking scripts and other kinds of removable content.
6. ImTranslator – ImTranslator is a very useful Firefox addon that provides easy translating service to users with some unique features such as text-to-speech converting facility,dictionary, virtual keyboard, spell checking feature, back translation etc. You can translate your content in over than 50 different languages.
7. Yoono – Yoono is one of the best Firefox addons that allows users to manage multiple social networking websites at one place. If you have multiple accounts in different social networking websites , this addon will help you to update your all social networking profiles at once. Currently this addon supports Facebook, Twitter, YouTube, Myspace, Flickr, Friendfeed, Linkedin , AIM , Google Talk, Yahoo chat and Foursquare.
8. BrowserProtect – If you want to protect your browsing data and internet connection, this great Firefox addon can help you to protect your browser from hackers.
9. Firebug – Firebug is one of the most downloaded Firefox addons that allows users to edit , monitor and debug CSS, HTML and Java Script in any kind of web page. One of the best tools for web developers.