How do chrome extensions proxy websites?

Question

Google Chrome

You need to understand the mechanism itself, because you want to forward them to VPN for certain sites, and work as is for the rest. Although maybe there is such a free extension and you should not fence the bike?

Answer 1

They install the PAC script with chrome.proxy.settings.set.
This JS file describes the logic for the browser how (through what) to establish connections.

Answer 2

There is a free AdGuard VPN extension, where you can configure which sites to use VPN and which not.