Block Proxy Browsers?

Question

Can Sophos Home UTM block proxy browsers such as Epic Privacy Browser, of other proxies configured in browsers. And can it block VPN? 
 
 Or will content filtering still work and block regardless of proxy or VPN?

DouglasFoster · Answer

Some security tools implement a host-based proxy, often with HTTPS inspection on the local PC. In this scenario, the host-based proxy takes effect before UTM. UTM should still be able to intercept the traffic because the proxy will be connecting on a normal port number. 
 If the PC is configured to connect to an Internet-based proxy, it will connect to that server using a non-standard port. TCP 8080 and TCP 3128 are the most common, but anything is possible. If you know the port number or the IP address, you could configure UTM to block the traffic, but it will be difficult to inspect it without blocking. If you don't know the IP address or the port number, the connection will probably work and will bypass the UTM proxy.