Or just use Whonix. Or better, Whonix in Qubes.
Why -H ""? AFAICT, it doesn't do anything.
Re:VPN leaks users’ IPs via WebRTC
by lallysingh on Wednesday March 28, 2018 @07:49PM
(#16703199)
Or just use Qubes on Tor
Using something as complex as firefox for anything important is just stupid.