MS Teams has a "green check" next to your name if you've touched your keyboard or mouse in the last five minutes and automatically sets your status to "away" if you haven't done so. I've had people at work use this to try and figure out if I'm working or not. It is a violating feeling, but also very similar to the "is your butt in the chair" way of management when not working from home, and I can see why managers like the feature.
For any of those suffering under this problem, have a look at caffeine[1], it simulates a keystroke on your laptop every 59 seconds.