Is there a way to hide Seen column?

Is it possible to add CSS classes to allow hiding the last seen time for specific users?

I want to hide it for my profile, because people send me messages and then are able to see when I’m last online. It’s just awkward if I don’t reply for a couple of days (not enough time for me to get to everything right away) but they can see that I’m online recently as they repeatedly check my profile, sometimes because I just have a tab open somewhere but am not checking the site.