Mystery Status Menu Icon (2018 MBP15, High Sierra)

[deeddawg]

I'm seeing the attached status menu icon in the menu bar today. 2018 MBP15 still on High Sierra, running in clamshell mode. No form of clicking on it seems to have any affect other than ⌘-click allowing me to rearrange.

I've searched here and Apple and come up empty handed.

Thanks for the help. I'm sure it's something simple.

 

[chown33]

Maybe System Preferences > Displays > "Show mirroring options in menubar..." checkbox (bottom of pane?)