Remove "Show Tab Bar" in View menu.

[pexner]

Please remove the menu entry “Show Tab Bar” in the View menu, because MDS’s main window has no tabs.

see:

https://stackoverflow.com/questions/39399553/how-do-i-disable-the-show-tab-bar-menu-option-in-sierra-apps

or

https://developer.apple.com/documentation/appkit/nswindow/1646657-allowsautomaticwindowtabbing?language=objc

or

https://forum.qt.io/topic/82609/remove-native-mac-menu-items-such-as-show-tab-bar