jpdBlock by Ky246

Its main feature is to block distracting sites such as youtube until you do reviews on jpdb.io. It works by giving points for every review done, and requiring you to spend points on websites you add as distracting.
It also punishes you if you don't do enough reviews in a day, and has options to make some changes to jpdb's reviews.

You can view the source code here:
https://github.com/KY246/jpdBlock

I can be contacted through a github issue.