Unable to delete User references from User Groups

Unable to delete User references from User Groups

This issue is fixed in versions 19.1.x and higher. For earlier versions, please use the following workaround.

1. Login as Administrator.
2. Go to User Group collection type configuration.
3. In the Contained Collection Types, turn ON the checkbox for "Users can be deleted from user groups".
4. Refresh All.

Though this specific setting is about deleting Users rather than References to Users, turning it ON may allow you to delete the references as well. It's not a prefect solution, but you may be able to delete references to users from user groups right away. You can have this setting ON temporarily, complete the deletion of your references, and then revert the configuration back.