Black screen occuring in fullscreen mode [CRASH]

A black screen is always occured when I switched to Fullscreen mode in game settings. It's been happening since patch 7.1 or 7.2 if I remember correctly. I remember there was a warning icon that says "ALT + ENTER to quit Fullscreen mode if your screen goes black in game" when that bug was discovered that time. I play League at 1366x768 resolution. Since the bug has been being occured I started playing in Borderless mode, which is kind of annoying to me because I have always liked the fullscreen mode. I was hoping that it would be fixed in a few patches but it didn't happen and include in patch notes. I hope it will be fixed soon. Thank you for reading :D.