League not accepting mouse input

Today I had a game start where League would not accept mouse input. I could not left or right click, nor scroll. I could open the shop with my keyboard but I could not purchase any items because I would have had to click them.

I tried exiting and re-loading into the game, even closing my client and re-logging and then re-loading. The only thing that fixed this was to restart my computer completely. Luckily I was playing with friends and they did not remake, but had I been playing alone I might have been slammed with leaverbuster.

Would be nice to figure out why this happened.