XQuartz does not respond to "Quit" events sent by the system. This means that it will not quit when someone right-clicks the Dock icon and selects "Quit". More importantly, if XQuartz is running and the user attempts to Shut Down the Mac, the Shut Down will not be able to continue because XQuartz will not quit. The only way to quit XQuartz is for the user to explicitly choose "Quit X11" from the File menu.
-- GitLab Migration Automatic Message --
This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.
You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/xorg/xserver/issues/803.