PanelAccessibleRole Available Panel Accessible Landmark Roles. Represents the ARIA role <code>complementary</code>. A section of the page, designed to be complementary to the main content at a similar level in the DOM hierarchy. Represents the ARIA role <code>Form</code>. A landmark region that contains a collection of items and objects that, as a whole, create a form. Represents the ARIA role <code>Region</code>. A section of a page, that is important enough to be included in a page summary or table of contents.