Blocking him is the best thing you can do. He is really a known troll, who has already been banned in other communities. He spreads dangerous misinformation, as you can see, and accuses people of racist without any proof. Furthermore, he basically just a bully who like to harass other people in every discussion he has. As @[email protected] said, don't feed the troll is the best approach.

Yes, do it in browser.