Maybe someone has the same problem...
i solved this way:
On camera management web pages, click Safari in the menu bar and you'll see the "Setting for this website" option, and click on it.
Deselect the "Enable content blockers"
OSX 10.13.4 - Safari 11.1 (13605.1.33.1.2)
NVR 7604NI-K1/4P V3.4.96...