You don't need adguard, just register with nextdns and use it as your system's DNS. By not supporting Linux you mean that it doesn't run with Steam's proton compatibility layer? Nowadays the games which don't work, usually are the ones using some form of aggressive anti-cheat measures. Online multiplayer stuff.
vii
joined 2 years ago
You need a distro with up to date kernel, for recent Intel laptops, and it will work out of the box.
There's Verso now too, a Servo based browser.
That's why I said to set it up globally, as system DNS, not just in the browser. Nextdns also allows you to pick the lists of filters. When it comes to Linux always check the game's compatibility through ProtonDB (unless it's native).