preventing ssh command from opening xquartz on every session

Question

Whenever I use ssh, after I type the password, xQuartz pop ups in the dock and terminal window looses focus. This happens even if there's no an X session. Why? How to prevent this behavior?

Answer 1

Solved by myself. XQuartz installation added a custom configuration for ssh in etc/ssh_config. I have just removed ForwardX11 yes and ssh won't open XQuartz anymore.