An illustration of how Mason handles overlapping feature annotations. The small box with the plus sign to the left of the row label indicates that overlapping feature annotations are present in that row. Clicking that box will expand the row such that all distinct feature annotations are displayed. In this case, a single mason viewer with multiple rows is shown. The user has clicked the box next to “Run: 471” and the row expanded to show all distinct annotations for that row in shades of magenta. The mouse pointer has been placed over a distinct annotation, resulting in the display of vertical lines showing the boundaries of that annotation across all rows and a tooltip describing that annotation.