with one of the available apps on the marketplace is the short answer. The long answer is, what do you want to achieve? Do you want to trigger transitions based when a field changes to a certain value or do you want to use a transition, provide a field value and want to happen things in the context of a transition/workflow? There are different solutions possible here. :)
so for anything in the context of a transition, I'd say have a look at the usual suspects on the marketplace (filtered for top-rated Jira Workflow apps) just to mention a few:
For automating in the context of a field changed event are different options available as well:
So maybe have a look at some of the products and make up your mind how you'd prefer to solve this and then have fun implementing it! :)
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