Mozilla Firefox is the best web browser as it provides its users an easy to use interface and many plugins and add-ons for safer browsing. Although Firefox is already a secure browser but some websites may spread malicious data while browsing. To get rid of such scripts here are best privacy and security add-ons for Firefox.
Torbutton : Torbutton provides a button to securely and easily enable or disable the browser’s use of Tor. It is currently the only addon that will safely manage your Tor browsing to prevent IP address leakage, cookie leakage, and general privacy attacks.
NoScript : The best security you can get in a web browser!
Allow active content to run only from sites you trust, and protect yourself against XSS and Clickjacking attacks.
WOT : Web of Trust (WOT) warns you about risky websites that try to scam visitors, deliver malware or send spam. Protect your computer against online threats by using WOT as your front-line layer of protection when browsing or searching in unfamiliar territory.
SwitchProxy Tool : SwitchProxy lets you manage and switch between multiple proxy configurations quickly and easily. You can also use it as an anonymizer to protect your computer from prying eyes.
Flashblock : Flashblock is an extension for the Mozilla, Firefox, and Netscape browsers that takes a pessimistic approach to dealing with Macromedia Flash content on a webpage and blocks ALL Flash content from loading.
FoxyProxy : FoxyProxy is an advanced proxy management tool that completely replaces Firefox’s limited proxying capabilities. It offers more features than SwitchProxy, ProxyButton, QuickProxy, xyzproxy, ProxyTex, TorButton, etc.
Dr.Web anti-virus link checker : This plugin allows you to check any file you are about to download, any page you are about to visit with online version of Dr.Web anti-virus.
BlockSite : BlockSite is an extension, which automagically blocks websites of your choice. Additionally, this extension will disable all hyperlinks to these websites, by just displaying the link text without the clicking functionality.
Secure Login : Secure Login is a login extension for Mozilla Firefox integrated password manager. Its main feature is similar to Opera’s (the browser) Wand login.
Redirect Remover : It removes Redirects like http://redirectremover.mozdev.org/?www.mozilla.org from Links and Images.
KeyScrambler Personal : KeyScrambler Personal encrypts your keystrokes at the kernel driver level to protect your information from keyloggers.
Temporary Inbox : This extension generates random disposable email addresses. You can use these email addresses for registration in forums, adult sites or wherever.
Panic Button : Panic Button quickly hide all browser windows with a click of a button.
Unhide Passwords : This extension shows the contents of password fields in cleartext (instead of the asterisks), to make that process a bit easier.
SecurePassword Generator : Helps you create truly unique and secure passwords. Access it from the tools menu.
Page Title Eraser : The Page Title Eraser (PTE) is a simple Mozilla Firefox extension which allows to hide title and icon (favicon.ico) of the selected tab. It provides more privacy at your workplace.
FFMyIP : Show user’s current IP in statusbar.
Fire Encrypter : FireEncrypter is a Firefox extension which gives you encryption/decryption and hashing functionalities right from your Firefox browser, mostly useful for developers or for education & fun.
Master Password Timeout : Locks the master security device after a predefined period of inactivity to prevent unauthorized use of saved passwords.
Close’n forget : Very simple add-on that closes the current tab and make Firefox forget about the visit.
LastPass Password Manager : LastPass is a free online password manager and Form Filler that makes your web browsing easier and more secure.