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Manual Group Adjustments: It is not feasible to manually add or remove the app's system user from custom groups due to its predefined role and permissions within the system. But you can do it programmatically.
Understanding Default Behaviors: Recognizing the default groups to which system users are added can help in troubleshooting troubleshoot and managing manage your Confluence site instance more effectively.
Consulting Documentation: For further adjustments and understanding of app permissions and functionalities, referring to the app's documentation and Atlassian's support resources is recommended.
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Understanding the limitations and default configurations regarding system users and group memberships can significantly help you manage your Atlassian applications more effectively. If you have any questions or require additional support, contacting contact Atlassian support or referring to the specific app documentation is advised for the most accurate guidance and request app user group reset and/or content indexing and clear Confluence application cache.