From an article by David Nield published in the lifehacker web site:

Just like apps on your phone, websites can request permissions inside your browser. Some of these permissions are pretty essential—like webcam access for video calling apps—but it's a good idea to run a regular audit of which websites and web apps have access to which permissions on your computer and phone.

These permissions can be pretty important, too: access to your location, for example. You'll probably want this turned on for a website that's delivering you a daily weather forecast, but it's not necessarily something you want every website knowing about.

Whatever browser you use, permissions must be explicitly requested and then granted by you—there's no way for them to be accessed surreptitiously. You'll see a pop-up whenever a new permission is requested, but as we'll show you here, you can also, at any time, check up on the permissions you've granted or blocked.

You can find instructions on how to check all the more popular web browsers at: https://lifehacker.com/tech/check-website-permissions-in-chrome-edge-firefox-and