Same for me. Happens after file transfer (move or copy) and progress dialogue opens.
Dialogue does not exit cleanly and retains 'focus' so you have no control over the app.
Also happens when running scripts, they will no longer exit cleanly.
Happens on local and network storage
MacOS high Sierra 10.13.6,, iMac 21.5"Late 2015.
Same for me. Happens after file transfer (move or copy) and progress dialogue opens.
Dialogue does not exit cleanly and retains 'focus' so you have no control over the app.
Also happens when running scripts, they will no longer exit cleanly.
Happens on local and network storage
MacOS high Sierra 10.13.6,, iMac 21.5"Late 2015.