I've seen a lot of new users adding "thank you" to their questions and then getting edited deleting the "thank you" thing. I've been getting frustrated about that and looked at post edit revisions, a lot of new users have "thank you" on their posts.
So, after then new users post more and more "Thank you" things on questions, then we, the old users get boring removing all of them in edits. But that seems not good. Can we add a warning if a new user has a "Thank you" in their question?