[MacTUG] any way (user template or MCX) to have 'display' icon in menu bar

[Dani Roloson]

AppleScript Editor:

-- Enable access for assistive devices
-- at the bottom of System Preferences -> Universal Access (any tab)

tell application "System Preferences"
  activate
  reveal anchor "displaysArrangementTab" of pane id "com.apple.preference.displays"
  tell application "System Events"
    tell application process "System Preferences"
      tell window 1
        tell group 1 of tab group 1
          click checkbox "Mirror Displays"
        end tell
      end tell
    end tell
  end tell
end tell

Or if you want the simple way:
Show displays in menu bar.
Turn on mirroring.

You could add
/System/Library/CoreServices/Menu\ Extras/Displays.menu 
to a login hook to get that in the menu bar.
(I used to need to add the Eject using Eject.menu.)