no, there's no such thing as a field permission. There was an issue for that (https://jira.atlassian.com/browse/JRASERVER-1330) , but it is closed and will not be implemented.
There are apps in the marketplace for that purpose, but I didn't try them yet:
In the past, Portfolio for Jira required a high degree of detail–foresight that was unrealistic for many businesses to have–in order to produce a reliable long-term roadmap. We're tur...
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