When executed on a User Extension table record, this action adds or removes a user account from the specified groups using the selected User Extension record. By default the User Extension is used in the Manage Users form. Designers can find this in the System Settings. The Modify User Groups action must be created on a form based on the Users table.
When executed, for each selected record, the user will be added to or removed from the selected Security Group. If a user has one permission and a different permission is added using the Modify Groups action, the user will remain in the first existing group as well.