Riot Client Problem (not launching/black screen) ?

Hello, it seems like that i have a problem that i would like to know if anyone else know how to fix it ? When i launch my Riot Client it launch but never appear on screen, only on background, and when he appear on screen it's all the time with a black screen like in the screen i provided. However, i know also that he is still working, as my updates and my games seems like having no problem when i launch the game by the icon on my homescreen... Im a little confused by that, so if anyone as a clue i'm taking it !