Rated 5 out of 5 stars

Leechblock is seriously the best addon I've found for the task. Once you figure out the customisation options and configure an appropriate set-up it really helps you focus. For context I am a third-year university student and Leechblock has proved invaluable for me in my studies.

This review is for a previous version of the add-on (0.6.5.1-signed).