Description of problem: The nm-connection-editor doesn't adhere to any quit shortcut such as the recommended Ctrl+Q. Version-Release number of selected component (if applicable): network-manager-applet-1.8.6-2.el7.x86_64
This is fixed upstream. Make sure you have at least nm-applet >= 1.8.12. Closing, as it will be fixed with the next rebase.