Title bar (let the OS draw this e.g. obeying users ability to choose Windows accent colour)
Menu bar (except on Mac where menu bars live at the top of the screen)
Navigation bar (with dedicated search box by default, and no hamburger menu - traditional menus are a more efficient use of space)
Bookmarks bar (user selectable, maybe have option to show only when user has added bookmarks to it)
Tab bar (looking like tabs, not buttons, clear dividers between inactive tabs so they don't look like "one thing")
Content area (let OS draw scroll bar elements or at least use OS supplied UI elements)
I switch between tabs A LOT, much more than using any other UI element, and my mouse pointer is often within the content area so having tabs at the "bottom of the toolbar stack" (as they were when they first appeared) would be a huge benefit for usability.