If you can tolerate the low number of users, not being a recommended extension (not "monitored" by Mozilla), and possibly a pseudonymous author, this is one of the most comprehensive malware and phishing page blockers. The most intrusive permission, "Access your data for all websites," is also optional. Search for more comments about this extension on the MalwareTips forum, where the extension author also contributes.

Amazing extension! The ability to choose security providers and such a rich selection of trusted vendors is an ultimatum defense against any browser threats!