The Extended project administration option allows project administrators to make changes to workflows and screens with certain limitations:

• Workflows cannot be used by other projects.
• Only statuses that already exist in Jira can be added to workflows. Project administrators cannot create new statuses.
• The existing status in a workflow can be deleted only if no issues in the project are currently in the status.
• Workflow transitions can be deleted from the workflow, but details such as properties, validators, conditions, post-functions, and screens cannot be changed.
• Only non-system screens, that is, screens created by Jira Administrators, can be updated.
• Screens cannot be used by other projects.
• Only existing fields, both custom and system, can be added to screens.