I have a scrum board where each issue has a series of sub-tasks (custom sub-task called Test Case), each defining a test case scenario for the parent issue.
As soon as I try to move a parent issue to the 'In Progress' column, a veto icon (circle with a bar across the middle) appears and I cannot drop the issue into the column. The project is using Simplified Workflow.
I can drag/drop the sub-tasks without a problem. I can also drag/drop issues with no sub-tasks.
Is this a limitation for parent issues when using a scrum board (we don't have this problem with the Kanban board)?