So it seems as of last week Firefox released a new version (52) which pretty much breaks all browser plugins apart from Flash (which is what rendered Chrome useless for this not so long ago). This means you may keep trying to install the WebComponents plugin but it does nothing. Thankfully there is a fix:
How to use Firefox v52 to live view Hikvision device
Hikvision's Overseas Website - On this site, you're after the file named 'Plug-in V3.0.5.26 build20150126 for Mac OS' (or a newer version). You may need to create an account to access the download, and so the below might be a preferable alternative. I know it's terrible and annoying to get this message over and over again when trying to use your Hikvision DVR, believe me I've been there and I know exactly the way it feels like, but you just need to work on two simple configuration to solve this problem, So, let's jump into this now. You can access your Hikvision cameras using the Chrome browser on your Mac. But the maximum resolution it'll show is 1920 x 1080 (looks horrible on a 5K iMac). And, the Playback function seems to be missing. We tested a Config change & Save in Chrome and that seemed to work OK. Hikvision Downloads. IVMS 4200 for PC (Legacy) IVMS 4200 for Mac. VSPlayer for Mac. Web Browser Plugin for Mac. Windows Media Player Plugin. V7.4.3 version Player for video stream from Hikvision product, suitable for play, edit of the recorded video file and live view of RTSP stream. VSPlayer for Mac Software Description: VSPlayer is a free media player designed for Mac OS.
1. Install the plug in first.
2. Open a blank page of Firefox and input about:config (where you normally type the web address)
3 Press Enter. Click on the, “I Accept the Risk” Button.
4. You will then be in the plugin section of Firefox.
Right click, then go to NEW from the dropdown list. You will have 3 options to choice from, you will need to select Boolean. Once you have done that, you will need to type the plugin name:
/addmusic4-57c7f6985f9b5829f435a9c4.jpg "Plugin")
plugin.load_flash_only
Click OK and choose “false” for the VALUE.
Web Video Plugin For Mac From Hikvision Password
5. Exit firefox and reload the DVR/NVR web interface to 'accept' to run the plugin at the top of the page (all being well).
There were a few other steps recommended past this, but we have found this alone to do the trick.