Since OpenCms 10, display formatters are a feature of OpenCms. The idea is to have a list content and in the content, you specify not only which contents are displayed in the list, but also which formatters to use to display the content. This separates formatting of the list (frame) itself and the displayed elements in the list.
However, display formatters can have element settings and be used as "normal" formatter as well when dropping a content to a page directly. These settings are of course available when the formatted element is dropped directly to the page, but not if the formatter is used indirectly by the list.
To solve this problem, element settings of display formatters can be configured to be shown with the settings of the list, either appearing as a setting of the list itself, or in a separate section in the settings dialog.
The following picture shows an example of the settings dialog for a list that renders the elements via display formatters that have settings shown with the list's settings.