Description

The 'Fields Required' checks whether values for specified fields are set for a given transition.

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You must select mandatory fields, when configuring the transition. For example:

JSU default behaviour is to apply the context settings, this means that a field that is required by this check, but having no valid context for the current issue, wont be checked. Thus you may select to ignore the context, in that case a field will be required by this check, even if its context is not configured for the current issue. 

For information on how to configure a check in JIRA, see the JIRA documentation.

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