With iCalendar’s RELATED-TO it is possible to create sub-tasks. This is a thread-like view of tasks, much like the mails have thread sorting.
- Implement RELATED-TO in evolution for Tasks, and probably events and memos, so that a task can be assigned to event
- Implement the RELTYPE parameter, so that tasks can have sub-tasks.
- Display tasks in the To-Do bar and in the tasks view hierarchically.
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