Someone elses masteries

Joined a Team Builder game with two friends and we were talking about various runepages. I checked her profile while we were searching for other laners and when I got back into Team Builder to make sure my masteries were correct I saw her masteries instead of mine. None of the names of mastery pages in that screenshot are any of mine, they're all from her profile after I checked it.

I made sure to not change pages on the chance that it was just a visual thing. When I got in game, I was still using the mastery page I had selected before checking her profile (as I had Thunderlords on and not her keystone), so in the long run it made no difference but it didn't allow me to change mastery pages if I wanted to without quitting and rejoining the Team Builder.