The sidebar is a reserved area along the side of a dashboard that you can use to give a dashboard more context, provide additional information to users, and so on. The sidebar is also used in interactive dashboards to host one or more selectors. A dashboard can only have one sidebar that is designed to fit its entire height. By default, the sidebar is a fixed size and positioned along a dashboard's edge. To configure the sidebar to be retractable, turn on the Collapsible sidebar toggle button.