Mouse doesn't stay in window - 1.6.0

     Hello, today I tried was going to play some Mineplex, and I went to look down, and my mouse pulled up the task bar. I then re-logged, and to my surprise, the glitch was still occurring. I soon restarted my computer, and it didn't work. I reinstalled the game... didn't work. It is a really annoying issue and it is ruining the combat aspect of the game.

 

~TwoCool

 

P.S. What separates this tread from the other treads with this issue is that those threads were from a year+ ago. It started happening today.