Emiks5
Pulling my weight
I agree that you do not have to disable UPnP for this doorbel, but for security reasons it is always a good idea to disable UPnP in your router.Yes, ONVIF use the same as http port unless it was configured to use a different port.
UPnP don't need to be either disabled or enabled for the doorbell to work if using cloud based app (scan barcode) service. But those required ports should not be blocked by the firewall if you are using your own app or recording to a hardware such as NVR.
The doorbell cloud I believe will create a network tunnel layer so it can directly communicate with the doorbell through the firewall. It's similar what VPN does but the tunneling on VPN is encrypted and cloud tunneling may or may not be encrypted because it only used to bypass a firewall policy which the doorbell is behind to communicate with.
Tunneling protocol - Wikipedia
en.wikipedia.org