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A pop-up dialogue box appears when you click on a task from the Gantt chart. 
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Expand
Use the Expand button to maximize the pop-up. 
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Result:
Listed information
The following information is listed in the pop-up:
task icon
task key
task summary
progress
status
start date
end date
period mode
in the scope of → the task has been added to the scope of listed boxes
Expand 
task ID
See changes
Opens the task history in the side panel.
The filters are automatically active - only the selected task is listed in the results.
Note: To see the side panel, you must collapse the pop-up. The side panel is not visible when task details are expanded.
Inline editing
Inline editing is available in the task details pop-up.