User autocomplete per_page does not work

https://gitlab.com/autocomplete/users.json?search=&per_page=2&active=true&project_id=13083&group_id=&skip_ldap=&todo_filter=&todo_state_filter=&current_user=true&push_code_to_protected_branches=&author_id=424775&skip_users=

Should return 2 users but that endpoint returns 20 users despite per_page=2