With Content Security Policy, or CSP, meanwhile, Firefox 4 ensures that cross-site scripting attacks can't infect a site such as through its comments section, he added.

I should also note that because Firefox's code is open, it's not subject to any vendor's preset patch schedule. Rather, its security is constantly being reviewed and improved.

8. HTML5

Firefox 4's new HTML5 parser and full support for Web video, audio, drag & drop, and file handling mean that it's capable of supporting the latest Web environments.

9. Multiplatform Support