Firefox extension NoScript prevents unauthorized web sites from running JavaScript, Java, Flash, or other plug-ins to keep your browsing sessions safe. The main purpose of NoScript is to protect yourself from browser or web vulnerabilities along the lines of this Gmail exploit by blocking untrusted scripts from executing in your browser. Granted, it may seem like a bit of a pain to enable all your trusted sites (though NoScript makes it simple to add sites to your whitelist in two clicks), but in the end an extension like NoScript turns Firefox into a very safe little browser. NoScript is free, works wherever Firefox does.

Download

Source: Lifehacker

downloadin Thx for info

Its good extension. I have read about it many times on net.

I can't imagine Firefox without NoScript

:)