Board Thread:Support Requests - Community Management/@comment-1038387-20131117204831/@comment-4519283-20131118202604

Just undo their edits and explain to them on their talk page/message walls about what the comment said, how to read the comment, etc. Like DEmersonJMFM said, they are likely using Visual Mode and don't recognize the comment.

Another possibility is that they are a bot, which I doubt, but posting on their talk page/message wall should automatically stop them until the problem is resolved.