ALTER IGNORE TABLE does not ignore duplicates as did in 10.1.23

In mariadb 10.1.23 for removing duplicates you can do a

ALTER IGNORE TABLE mytable ADD UNIQUE (bean_id, field, history_date, value, deleted);

Duplicates for this unique key will get removed.
In mariadb 10.2.6 you get an error:
ERROR 1062 (23000): Duplicate entry '123456-price-2016-0' for key 'bean_id'

So the "IGNORE" seems to be ... well ignored.