In 20.4.52 version of Gantt Chart, if the child has 1 day duration( as unscheduled task), corresponding parent taskbar won't be rendered. -
Pn73cs (forked) - StackBlitz
but In 25.1.35 version of Gantt Chart, if
child has 1 day duration(as unscheduled task), corresponding parent taskbar is rendered based on the child dates. - Pn73cs (forked) - StackBlitz
If the parent contains only unscheduled child tasks then the parent task should not render.
Note: Child task has no start and end dates, but the parent taskbar rendered by itself