It doesn't say how they measure it. Some browsers identify as using Windows. Many people also use multiboot with Windows. Having Windows preinstalled also doesn't mean you're using it.
Tribler is an open source decentralized BitTorrent client which allows anonymous peer-to-peer by default. Tribler is based on the BitTorrent protocol and uses an overlay network for content searching
From what I understood is that the functionality that pastes selected text with middle-click is coded deep in the Linux kernel, so it doesn't even use a clipboard and it would be hard to get rid of this functionality. As others mentioned, using normal copy-paste commands (ctrl+shift+c) shouldn't be a problem because it uses a clipboard.
Apparently they need to ask for consent before detecting whether you have an adblocker, according to EU law. I assume you'd be safe when you use a plugin like Consentomatic or I don't care about cookies and you just don't log in to Google.
You could just open everything in a new tab