Mouse cursor and chat Bug (2017)

So i've noticed that this was talked about, but there were no solutions for it, and it makes the game frustratingly harder:

I have two monitors. Sometimes I Alt+Tab away from league in Borderless mode, to change a song, or chat in Skype while i'm dead. Sometimes, the mouse cursor changes to the Desktop cursor, and will never change back to the LoL cursor. This breaks the chat, so that when I press Enter, nothing happens. I cannot communicate any more as if I was chat banned. My ping hotkeys are all wrong as well when this happens. I signal I'm 'on the way,' but it says 'be careful' instead. This can be confusing to my team. It makes using skills harder as well, as the cursor never changes, and is smaller. It often gets lost in team fights, and that messes with my overall play.

Things I have tried: -Closing client, Deleting 'PersistedSettings.json' and starting a custom game, but the cursor remains broken. -Running the game as Admin, cursor still broken. -Resetting game defaults, no fix. -Restarting computer (50/50 sometimes fixes it, sometimes doesn't.)

I've never had this problem until the past couple months. What happened? Can an Admin PLEASE assist me with this, or if there is a user who has fixed this problem, it would be greatly appreciated.

Thanks in advance.