Post Game - Issue adding friends

Pretty sure this falls into the realm of gameplay bugs, but not 100%.

Over the past few games, regardless of role, champing or game length, I've noticed that I've been unable to add someone directly from the post-game screen. Not sure if this is a personal client issue or a larger bug. Not really game breaking but a bit of a shame when I play a good game with someone I'd really like to add and I can't do so without relying on using the recently played list.