Why does the javascript navigation object return so many browsers?

Question

JavaScript

I'm trying to find out the user's browser. I display the value of navigator.userAgent, I get the string - "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.91 YaBrowser/16.4.0.6174 (beta) Safari/537.36"
Instead of the expected YaBrowser/ 16.4.0.6174 (beta), how to understand which browser is actually used?

Answer 1

webaim.org/blog/user-agent-string-history

Answer 2

These are priorities,
like I "Mozilla/5.0 (Windows NT 6.3; WOW64)"
don't you know that? then I "AppleWebKit/537.36 (KHTML, like Gecko)"
don't you know that? then I "Chrome/49.0.2623.91"
do not know this? then I "YaBrowser/16.4.0.6174 (beta)"
do not know this? then I "Safari / 537.36"
Yandex browser uses the engine of someone else's browser, because it works there - it also works in yab. But most programs have not heard anything about yab, so he presents himself to them as "I'm Mozilla / 5.0 (Windows NT 6.3; WOW64)"

Answer 3

I don't have YaBrowser so I'm not sure but theoretically

navigator.appCodeName

should help you