For a while, I've been having my suspicions about a certain power user that often downvotes my questions - both here and on MO. Now, I know for certain this user has downvoted a question of mine at least once. They also often just give unhelpful, snarky comments. Generally, I find this type of behaviour very demotivating.
I'm not quite sure what to do with this. Obviously, this person is quite intelligent. The way they work is more subtle than, say, a downvoting troll. In the latter case, the downvotes are usually rectified. However, when the downvotes are more sparse and chosen at strategic moments in time, it is harder to notice and the behaviour is more difficult to address.
What should one do in this situation? Is it possible to "block" certain users from viewing your profile, and your questions in the feed? I've kind of had it with this person's negativity and I'm not interested in engaging with them any further.