I have a MacBook Pro 15" 2013 with an LG 34" and DELL 24" monitor attached. Since the most recent update, when I drag my Win7 development machine onto my LG monitor and then try and resize the window it immediately flips back to the macbook screen, often with a bizarre aspect ratio. Bizarrely my desktop-apps Win10 machine exhibits the same behaviour but always flips back to my DELL monitor. It seems that resizing confuses it and sends it back to the screen it was opened on. Result is I can't use either machine on my main 34" display. Any ideas?!
