The macOS’s new version 2.25.20, compatible with Catalina. It will happen on the Catalina version. The App connects to the NVR in the local network, the Catalina will pop up a warning window. It won’t hurt the macOS computer.
1. When you log in to your NVR, there is a popup window that shows on the desktop. You will click ‘OK’.
2. Click on ‘Allow Anyway’ and on ‘App Store and identified developers’.
3. Or popup window shows the following screenshot, you will click on ‘Open’.