Automatic Window Tabbing in macOS Sierra causes a menu item called "Show
Tab Bar" to appear under the Window menu in the menu bar. Selecting this
option causes a double-title bar effect as there is no option in OpenRCT2
to make new tabbed "documents". This double-title bar can be untoggled
by selecting "Hide Tab Bar".
I don't think OpenRCT2 is going to become a tabbed document-oriented
themepark simulator anytime soon. Thanks, but no thanks Sierra.
References:
* https://codereview.chromium.org/2325313002/
* https://hg.mozilla.org/releases/mozilla-aurora/rev/385b9ea08ff7
* Use better Obj-C styling for macos_disallow_automatic_window_tabbing()
