Multi column foreign key on same table fails depending on primary key definition

The following table definntion

CREATE TABLE `test` ( `id_art` int(10) unsigned NOT NULL, `old_id_full` int(10) unsigned NOT NULL, `old_id` int(10) unsigned NOT NULL, PRIMARY KEY (`id_art`,`old_id_full`,`old_id`), KEY `ttt1` (`id_art`,`old_id`), CONSTRAINT `tttt1` FOREIGN KEY (`id_art`,`old_id_full`) REFERENCES `test` (`id_art`,`old_id`) ON UPDATE CASCADE ON DELETE CASCADE) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_general_ci CHECKSUM=1 ROW_FORMAT=COMPRESSED;

with

insert into test values(1,1,1);

returns

ERROR 1452 (23000): Cannot add or update a child row: a foreign key constraint fails (`diss`.`test`, CONSTRAINT `tttt1` FOREIGN KEY (`id_art`, `old_id_full`) REFERENCES `test` (`id_art`, `old_id`) ON DELETE CASCADE ON UPDATE CASCADE)

while this table definntion

CREATE TABLE `test` ( `id_art` int(10) unsigned NOT NULL, `old_id_full` int(10) unsigned NOT NULL, `old_id` int(10) unsigned NOT NULL, PRIMARY KEY (`id_art`,`old_id`), UNIQUE KEY `ttt1` (`id_art`,`old_id_full`,`old_id`), CONSTRAINT `tttt1` FOREIGN KEY (`id_art`,`old_id_full`) REFERENCES `test` (`id_art`,`old_id`) ON UPDATE CASCADE ON DELETE CASCADE) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_general_ci CHECKSUM=1 ROW_FORMAT=COMPRESSED;

does not return any error (this is the expected behavior). So it seems it depends on the third column for the PK definition in the first example, or am I just missing something?

Thank you.