It seems like manual Socks5 Tor proxy configuration on Icecat reveals that it's not using the Tor browser but if one uses FoxyProxy to manage Tor, it pretends to use the Tor browser. I use Clean Links, Decentraleyes, FoxyProxy Basic, HTML5 Everywhere, HTTPS-Everywhere, No Resource URI Leak, Privacy Settings, Random Agent Spoofer, Self-Destructing Cookies, uBlock Origin, and uMatrix extensions. I don't know if using [code]torsocks icecat[/code] would mask Icecat as Tor Browser via ip-check.info