Yes, you can get the parent object of the issue and easily transition it to open state in the post-function (but only do it after checking that the current issue is a sub-task if sub-task and parent share the same workflow)
Here's the code in the answer, you need script runner installed.
As a Jira power user, I was at first doubtful that Trello could benefit my workflow. Jira already uses boards (ones you can customize!), so why would I even need to use Trello?! In this post you will...
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