uMatrix is without a doubt used as a commercial trade mark. Again, commercial doesn't mean money is involved. It's also still used by the owner, as it's still

uMatrix is without a doubt used as a commercial trade mark. Again, commercial doesn't mean money is involved. It's also still used by the owner, as it's still listed in several extension stores. Trademark protection also doesn't end over night. Trademarks are generally protected for a few years after the owner ceased to use it. Also, one should keep in mind that trademarks aren't primarily an intellectual property concept like patents and copyrights. Their main purpose is to protect consumers from copycats and fake products.