Feanor

First of all, beware the extensions you install. Extensions can be poorly coded and bugged or even made on purpose to introduce any sort of bad stuff on your computer. Extensions can do pretty much everything once you install them.

Then, NoScript promises to protect your computer by disabling javascripts in Web pages. The problem with it is you have only two options, disable everything or enable everything with a blacklist/whitelist of domains. Once you enable, adding the site to the whitelist, NoScript is mostly useless.

Last thing, NoScript author is getting money from advertisement in his Website. Since you can block the advertisement with the ADBclockPlus extension, it changed NoScript installation to hack ADBlockPLus in order to "unblock" the advertisement from NoScript. This is VERY wrong among extensions and it is the usual bad policy to make changes on people's computers without asking permission. Even worse considering NoScript is sold as "security" software.

In short, do not install NoScript, technically it does not add any real security to your Firefox and its author cannot be trusted. To get better security you just add this line to your ADBlockPlus list of rules:

http://*$script,third-party

It will block all scripts that come from domains other than the one you are browsing. Then you can whitelist those domains you really really need. with something like:

@@http://www.blogger.com/widgets/*$script