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.
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
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