Viewing someone's champions mastery BUG

Hi. I just notice there's a bug viewing someone's champions mastery. Basically, you just view their profile, then click your own profile page (the tab next to store) then press the champions tab. Basically, the champions are yours but the mastery aren't. Oh btw, you need to quickly press your own profile page then the champs page. Not sure if it's a bug, or it's intended.