According to those screenshots officially published by Steinberg, Dorico keeps using a silver title bar with its dark theme. I am wondering whether a dark title bar could be available for users, matching the macOS Dark Menubar and the default Dorico Dark theme. // Note that Final Cut X, Logic Pro X, iMovies (since late 2013), Pixelmator and Photoshop CC are all using dark titlebars under macOS.
If you switch on the ‘Use dark menu bar and dock’ option in the General pane of System Preferences, Dorico’s menu bar, like all Mac applications, will follow the operating system preference. The colour scheme Dorico uses within its own windows is not in any way connected to the preferences you can set in either Windows or macOS for colour schemes.
I am going to put this discussion on hold until the Dorico 1.00 is on sale.
I see that you are referring to the window title bar, not the menu bar: apologies for misunderstanding your original post.
We are not custom-drawing the window furniture in Dorico. We may add this at some point in the future, but not in the near term.