The name or IP address of a proxy-based firewall.
This property specifies the IP address, DNS name, or host name of a proxy allowing traversal of a firewall. The protocol is specified by FirewallType: Use FirewallServer with this property to connect through SOCKS or do tunneling. Use ProxyServer to connect to an HTTP proxy.
Note that the add-in uses the system proxy by default. To use a different proxy, set ProxyAutoDetect to false.