entrypoint.sh's turn_server fallback only appended :TURN_PORT when TURN_SERVER was completely unset — a TURN_SERVER carried over from an older install (or set to a bare host by hand) passed straight through with no port, so the Sipnetic QR export's "st=turn:user:pass@host" field ended up missing the port entirely. Append it whenever the configured value has no colon at all, not just when it's empty.