I’ve never seen any content there that “advocated violence”.
They moved to a new registrar, but it’s only a matter of time before the trolls start flagging that company as well.
On Wikipedia’s Stormfront page:
“In August 2017, Stormfront’s domain name was seized by its registrar for “displaying bigotry, discrimination or hatred.”[12]
The site came back online on September 29, 2017. As of October 2017, services to keep the site online were provided by Tucows, Network Solutions, and Cloudflare.[56]”
I dislike Stormfront, but those domain registrars might be worth a look.