Add feature to collapse/group all completed tasks on scrum board
For stories with a large number of tasks its can be tiresome to have to scroll down to find tasks.
To aide visualization I would suggest adding an option to the scrum board that allowed all completed tasks to be represented by a single 'grouped' image.
for instance selecting at the scrum board level a 'group all completed tasks' option would change the display to show a single GUI widget to represent completed tasks for that user story.
The user would have the option to expand/collapse the grouped completed tasks at an individual story level
We have Column minimize option to hide columns.