You Need To Install Xquartz 2.7.7 Or - Higher First

No. Only GUI-based X11 applications (like xclock , gvim , matplotlib plots with TkAgg backend, or remote apps via SSH) require it.

If you’re seeing the error when using ssh -X user@server , your local XQuartz might not be allowing remote clients. you need to install xquartz 2.7.7 or higher first

If XQuartz is running, you should see something like /private/tmp/com.apple.launchd.xxxx/org.xquartz:0 or just :0 . If DISPLAY is empty, launch XQuartz manually from the Applications folder once, then reopen Terminal. matplotlib plots with TkAgg backend