How to hide subtasks in Done AFTER parent task is Done

[anton_vorush]

Please help me with writing proper JQL for this. 

Sometimes tasks have lots of sub-tasks, and it is perfectly OK for them being on the board during work on them. However, with time sub-tasks will be resolved to Done column. And as soon as parent task is also finished and moved to Done - there is no sense to keep and shop all its subtasks there.

I tried something like 

issuetype in (Sub-task, Defect) AND issueFunction in portfolioChildrenOf("Status = Done") 

However without success.

[Joy RK]

Just to clarify the question:

• Do you want to be able to display subtasks on a board?
• Do you currently implement an automation to close out all subtasks when the parent ticket is done?
• OR Parent ticket is automatically closed when all subtasks are done)
• Do you want to exclude subtasks from your board?