I have been fighting the same problem for ages, but somehow I got it to work...
Not sure what helped, but I now have a live view on all camera's using the web interface on my Macbook.
This is my setup:
I have three camera's, all are Hikvision DS-2CD2155FWD-I.
Just updated the camera's, all are now running the latest firmware released September 2019, which is ''V.5.6.3 build 190923''.
Running OS Catalina 10.15.3.
Running two browsers: Safari 13.0.5 and Opera 66.0.3515.44.
I can watch the live view on both browsers.
After I was sure everything was up to date, I only could watch a live view on 2 out of my 3 camera's. After playing around, I figured that the only camera which didn't work, had the ''rotate'' function turned on. So I turned it off, and now I am able to watch a live view on that camera as well (sideways...).
It is not a full quality live view, but good enough.
Finally I am able to change setting like ''line crossing'' etc., since the iVMS software doesn't allow me to draw lines.
Attached the screenshot of the working live view on Safari. One of the camera's only worked when I turned Rotate OFF in the settings.
Today I went to my father in law (who has the same camera's) and also updated the camera's etc. And I also succeeded getting the live view to work after months...
Ps. The camera firmware update could only be done via iVMS. Via the web interface, the ''browse'' button simply didn't respond... So I installed iVMS software, and did the firmware update via iVMS. After the firmware update, the live view was there. Magic.
Thanks - maybe I need to wait for a firmware update to get it working.
At least the new iVMS-4200 is mostly working on my Mac with all live view windows now behaving well. However, it seems to have lost some config parameters so I have no brightness/WB etc settings to adjust! Ironically, these settings are accessible via my web browser but without a live view display, they are sub-useful.