JSON_TABLE: Values for regular columns are truncated for no reason

+------+

| a    |

+------+

| fo   |

+------+

1 row in set (0.002 sec)

MySQL [test]> select * from json_table('{"a":"foo"}',"$" columns(a varchar(8) path '$.a')) x;

+------+

| a    |

+------+

| foo  |

+------+

1 row in set (0.001 sec)

MariaDB [test]> select * from json_table('{"a":"foo"}',"$" columns(a varchar(12) path '$.a')) x;

+------+

| a    |

+------+

| foo  |

+------+

1 row in set (0.002 sec)