Rule for VMWare Horizon traffic


I'm trying to figure out the correct portfilter setting to connect to a VMware Horizon Server. Documentation says Port 443 and 8443 with UDP and TCP. But the connection get stuck. When I create a rule which allows all traffic to the server, everything works fine. But the logfile (logging for this allow rule enabled) also shows only 443 and 8443 for the connection. Maybe somebody here has experience with Horizon Server?

Hardware: UTM SG135 with FW 9.718-5, only Firewall and IPS, no Webfilter