Standalone borderless window doesnt get keyboard input (Mac)

Hi everyone,

Using the command line argument -popupwindow I can run a Mac standalone window borderless perfectly. However the key inputs from the keyboard won't work for some reason. If I run the app in windowed or fullscreen mode all the key inputs work as expected but when I run borderless nothing happens, I just hear a mac error sound every time I press a key.

I'm really not sure if that's a bug or a problem from OS X (I tried El Capitan and Yosemite).

Thanks!