Excellent, I came close to writing something like this myself to redirect reddit’s glacial new mobile site to good old i.reddit.com. I appreciate the Firefox support.
A word of warning, by default it’s set to pull a redirect list from someone’s personal GitHib Gist. IMO that should be opt-in, the potential security consequences are just silly.
Might be worth opening an issue for that. :)
Something similar is Decentraleyes, which loads JS libraries locally, leading to faster page loads and a little more privacy. It’s fully baked and works well. If you use HTTPS Everywhere on Chrome then there are some settings to change but it guides you through those.