you can't define specific permissions for specific custom field. As a workaround, you could remove this field from the edit screen and add a specific transition with a screen that include just this field.
Moreover, you should add a condition for this transition so that just specific users/groups can perform it.
Hope this helps.
I’m a designer on the Jira team. For a long time, I’ve fielded questions from other designers about how they should be using Jira Software with their design team. I’ve also heard feedback from other ...
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