- Arguably the dock, though it's probably contentious - Ubiquitous instant search (e.g. Spotlight) - Gesture-based automatic tiling of windows to left/right side of the screen, tiling presets - Smooth scrolling, either via scroll wheel or trackpad - Gesture-based multi tasking, etc - Virtual desktops/multiple workspaces - Autosave - Folder stacks, grouping of items in file lists - Tabbed windows - Full-screen mode - Separate system-wide light and dark modes - Enhanced IME input for non-latin languages - App stores, automatic updating - Automatic backup, file versioning - Compositing Window Managers (Quartz, Compiz, DWM, modern Wayland compositors...) - The "sources bar" UI pattern - Centralized notification centers - Stack view controlelr style navigation for settings (back/forward buttons) - Multi device clipboard synchronization - Other handoff features - Many accessibility features - The many iteration of Widgets - Installable web apps - Virtual printers ("print to PDF") - Autocomplete/autocorrect - PIP video playback - Tags/Labels - File proxies/"representations" - Built-in clipboard management - Wiggle the mouse to find the pointer
None of these can be said to be at their final/"perfect" form today, and there are hundreds if not thousand of papercuts and refinements that can be made.
The real issue is probably due to management misunderstanding designer's jobs, and allocating them incorrectly. The focus should be more on the interactions and behaviors than necessarily on the visuals.