Suggestions to fix the alt-tab issue?

I alt-tabbed out of the loading screen, and of course it refuses to let me play the game now. I already restarted the laptop and shut down. Any other ideas?

Edit: Doesn't matter, they already surrendered and I already got the AFK thing. thanks, Riot. 20 minutes of my life wasted, and I get punished.

Edit Again: Problem persisting to custom games. Interesting.