If you're just a rando who isn't likely to get specific attention from someone like the NSA or other state-backed threat agents, then the answer is that if ever

If you're just a rando who isn't likely to get specific attention from someone like the NSA or other state-backed threat agents, then the answer is that if everything is behaving normally that you're not compromised. For the bulk of people if someone breaks into your personal device they're going to start using it for something. You'll see unusual utilization, your proxy settings on your browser will get changed, you'll just be hit by a ransomware attack and your drive will be encrypted and you'll be locked out, etc. They're after the bulk of the users out there and they don't need to be particularly stealthy about anything. Of course if you have large quantities of BTC or something then the answer is to get it off of your personal machine and setup a cold wallet that cannot be hacked, and stop installing clever looking crypto shit on your machine.