The title of the Profile page is "Profile of" if the user didn't fill in his First and Last Name

Currently when an user doesn't have the First and Last Name filled in the title of the Profile page is simply "Profile of". We could change the title to something like "Profile of [username]" until the user fills in his details. Screenshots attached.

I see that on 4.5.4 this bug doesn't exist. I've attached screenshots.