About NoScript
NoScript is a free, open source extension by Giorgio Maone that blocks JavaScript and other active content unless you trust the site. Its pre-emptive blocking is meant to stop exploits before the page can run code, and one click enables scripts for a site, temporarily or for good. It is also built into Tor Browser, which says something about its standing among security people.
The cost is effort. Most modern sites need scripts, so on day one you will meet many broken pages and prompts, and a site often relies on several third-party domains. People who accept that get the strongest control over what runs in their browser, a different approach from list-based blockers.
Firefox is where it works best. The Chrome version is Manifest V3 and lacks the blocking and response-filtering permissions the Firefox version requests, because Chrome does not offer them. Chrome shows about 100,000 users and a 3.9 rating, Firefox about 240,000 users and 4.4. It is supported by donations. If you are happy to make a few clicks per site, it is a real security gain. If not, skip it.
Pros and cons
- Blocks scripts and other active content until you allow a site
- Open source and funded by donations
- Built into Tor Browser
- Actively updated: Firefox version 13.6.37 shipped on 1 November 2026
- Breaks many sites until you allow their scripts
- Takes patience to configure, and some sites need several domains allowed
- The Chrome version cannot use some Firefox-only APIs
Permissions
It can read and change data on all websites, watch navigation, and inspect and filter requests, which it needs to stop scripts before they run. The Firefox version also asks for blocking and response-filtering access, and the Chrome version asks for the debugger permission.
