Issues containing issues: Parent-child issue relationship
- Subissues, similar to related issues #2001 (closed).
- A given issue can have any number of children subissues.
- A given issue can have at most one parent issue.
- A given issue can have at most one parent epic.
- Besides indicating the tree structure in an issue below the description (see mockup), there is automatic closing functionality:
- When all the immediate children of a given issue is closed, the given issue is automatically closed.
- So a cascading up event can happen.