View updateable when documentation says it should not be

Documentation suggests that a view will not be updatable or insertable if it contains an outer join, however the attached example containing a view with a left join allows updates on the view but not inserts.

https://mariadb.com/kb/en/inserting-and-updating-with-views/#inserting-with-views

This is inconsistent and either the documentation is wrong or the server is behaving incorrectly.