Installing and uninstalling our apps is a standard procedure, and you can do that via Universal Plugin Manager (UPM). 

Uninstalling via Universal Plugin Manager

For more information about uninstalling via UPM, see UPM documentation.

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4. Locate User Group Picker Pro in Pro™ in the list of your installed apps or use search. 

5. Click Uninstall.

Manual Uninstalling

In addition to using UPM, you can also uninstall the app manually.

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1. Go to the folder where Jira server has been installed.
2. Access <JIRA_APPLICATION_DATA>/plugins/installed-plugins and manually delete User Group Picker PRO PRO™ app.
3. Restart Jira server.