The Malwarebytes Browser Extension for Firefox serves to protect you from a few web-based maladies: tech support phishing sites, for example, that remake themselves and elude conventional detection, or scam behaviour. It also improves privacy on the web with a few filters. Of course, as the name might imply, this browser add-on works best when it's partnered up with Malwarebytes' own product. On its own, the add-on can protect you from some web-based threats, but Malwarebytes Anti-Malware (and its pro equivalent) come highly recommended.