I've been having this problem on Math Stack Exchange — and it has to do with the fact that I can't really tell when somebody is commenting on their own question, usually in response to another comment, in response to an answer, or clarification for the question itself.
For example, on YouTube, when somebody leaves a comment on their own video, their username is highlighted so you're easily able to tell that this commenter is also the person who made the video.
MSE, on the other hand, does not have such luxuries. And, arguably, knowing when somebody comments on their own question is even more important on MSE than on YouTube. Yes, I know, you can just look at the usernames, but when's the last time you looked at a question and went straight to the username? Usually people look at a comment and they need to scroll back up to the question to tell who posted it.
Maybe it's not a HUGE issue, but I believe that it would help with clarity if when somebody comments on their own question their username appears highlighted. Thoughts?