NoScript - Firefox
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.
Winner of the "2006 PC World World Class Award", this tool provides extra protection to your Firefox
Such a preemptive approach prevents exploitation of security vulnerabilities (known and even unknown!) with no loss of functionality... Firefox
is really safer with NoScript
NoScript - Firefox Website - NoScript - Firefox