In OTCS 20.3 the smart view header message persists despite being set to not permanently display.
I have set the smart view config setting as unchecked for header messages. The header persists when you add a document and doesn't go away until closing via the X. On other actions, the header automatically disappears - in a folder click the select box on an item and in the top menu click Copy Link. The header message opens for about 10 secs and closes.