The [[Troubleshoot Firefox issues caused by malware]] article has this Apple Support link for Mac users concerned about malware: *https://discussions.apple.com/docs/DOC-3291 ''Harden your Mac against malware attacks'' On privacy issues related to tracking and Firefox, see: * [[How do I turn on the Do-not-track feature?]] * [[Disable third-party cookies in Firefox to stop some types of tracking by advertisers]] Hope that helps.

P.S. I see you are still using Firefox 25. You should update Firefox to the latest version, currently Firefox 26, to take advantage of recent security fixes and other improvements. See *[[Update Firefox to the latest version]] * http://www.mozilla.org/security/known-vulnerabilities/firefox.html