Mode Highlight is an interface add-on that automatically changes the color of the 3D Viewport header depending on the active workspace mode. It provides immediate visual feedback to help users quickly identify whether they are working in Object, Edit, Sculpt, Pose, Vertex Paint, Weight Paint, Texture Paint, or Grease Pencil Draw mode. Users can customize the specific color for each mode through a dedicated panel in the viewport sidebar, and these color preferences are saved globally across all projects.