WWDC25: AppKit toolbars in the new design system

The new design system transforms the appearance of a Mac window, altering the window shape and framing its key structural regions in glass. One of those regions is the toolbar. In the new design system, toolbar elements are placed on a glass material, and the entire toolbar appears to float above the content, enhancing the sense of hierarchy within the window.The glass also brings controls together in logical groups. Since they all represent singular actions, AppKit automatically groups multiple toolbar but ...