In which browser is the extension installed?

Question

Google Chrome

There is a universal extension that is suitable for all browsers based on Chromium.
Depending on the browser, this or that link is displayed in the extension.
Is there any API or other way to find out in which browser the extension is running?
Ideally, you need to get a link to the store (Chrome, Opera, etc.) where the extension was installed from.

Answer 1

navigator.userAgent available?

Answer 2

You can put in the Chrome store and in the Opera store 2 different versions of the extension, differing in one constant