A modal dialog is a window that appears over the primary screen to present supplementary information or interactive fields. While the dialog is open, the content behind it becomes inactive until the dialog is closed or dismissed.

When a dialog opens, the initial keyboard focus should be placed on the first focusable element within the dialog as per standard web design. In Constellation modal dialogs, however, initial keyboard focus is set on the first editable field, if one is present, rather than on the action buttons in the dialog header.

This design choice is intended to improve efficiency for business users and frequent users of the application, allowing them to begin entering form data immediately when a dialog opens. Screen reader users will still hear the dialog’s name and role announced when keyboard focus enters the dialog, providing sufficient context. Keyboard users can navigate back to the header button(s) or use equivalent actions available in the dialog footer should they need to close the dialog.