On macOS High Sierra I have install the "emacs-mac" Emacs port via homebrew. The Emacs version now is 25.3.3.
When starting up Emacs I get this strange tab in my Emacs frame:
I have set the Document tab setting "Prefer tabs when opening documents" in the Dock Preference pane to "Manually". I still have this useless tab.
How can I get rid of it?