WINDOWED issue LOCK THE MOUSE PLEASE!

WHY is it NOT possible to LOCK the mouse to the window, it is utterly useless to have the mouse go outside the window it is just irritating!!! There are so many bugs happening right now with this game I kind of wish I had not got involved NOT HAPPY… It really needs work and it was released way to early, I have supported it as a backer but my patience is wearing VERY thin now. I just can not get this to work for very long, goes well for a few hours then starts to come apart at the seems, is their light at the end of this very dark tunnel or are we going to actually see something that functions well? And PLEASE PLEASE PLEASE lock the dam mouse to the window it REALLY is not hard to do!!!