Can I create a filter to show all stories that are open, and all their subtasks regardless of the status of the subtask? I'd like to do this without having to purchase a plug-in.
Unfortunately, without going for a paid app, there's no JQL that will list you all the children without being specific as to which parents.
There's a couple of app that could help you do this such as Search Linked Issues and _JQL Tricks PluginBut I only have experience with JQL Tricks Plugin and it does the job well.
With J-Tricks, it goes like :
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