JSON_OBJECTAGG skips the length limit of group_concat_max_len

SET SESSION group_concat_max_len=32;

CREATE TABLE t(k VARCHAR(8), v VARCHAR(64));

INSERT INTO t VALUES

  ('a', REPEAT('x', 20)),

  ('b', REPEAT('y', 20));

SELECT JSON_ARRAYAGG(v) FROM t; -- ["xxxxxxxxxxxxxxxxxxxx","yyyyyyy"]

SHOW WARNINGS; -- Warning	1260	Row 2 was cut by json_arrayagg()

SELECT

  JSON_OBJECTAGG(k, v),

  OCTET_LENGTH(JSON_OBJECTAGG(k, v)),

  OCTET_LENGTH(JSON_OBJECTAGG(k, v)) > @@group_concat_max_len

FROM t; -- {"a":"xxxxxxxxxxxxxxxxxxxx", "b":"yyyyyyyyyyyyyyyyyyyy"}	56	1

SHOW WARNINGS; -- empty