I was downloading extensions by using fetchExt.sh script that I got from a topic in forums. Rich pointed me towards that and it has been very helpful so far but I just realized that missing dependency is caused by that script only.
Also, I was trying to load just `libv4l2` but from your last response, I realized I should be using `v4l2-utils` instead.
This time, I loaded extensions via internet, using tce-load (long story, was earlier developing on Raspberry Pi Zero, so had no networking options but now using Raspberry Pi 2B) then I was able to download that missing dependency.
This resulted in atleast the browser prompting for granting access to camera, but it shows 3 cameras, and none of them works when I select one (I get abort error in browser console). Here's a screenshot with their names -
https://imgur.com/a/URfh58kWhen I try in terminal using v4l2-ctl or ffmpeg command, it says `cannot open device /dev/video0, exiting`