resultset changed with subselects without changing data

CREATE TABLE IF NOT EXISTS  `t1`  ( `id`  VARCHAR(50) NOT NULL) ENGINE=Columnstore DEFAULT CHARSET=utf8; 

CREATE TABLE IF NOT EXISTS  `t2`  ( `id`  VARCHAR(50) NOT NULL) ENGINE=Columnstore DEFAULT CHARSET=utf8; 

set max_recursive_iterations = 10000000;

INSERT INTO `t1`  (

with recursive series as (

select 1 as id,LEFT(MD5(RAND()), 36) as r1 union all

select id +1 as id, LEFT(MD5(RAND()), 36) as r1  from series

where id < 100000)

select r1 from series);

insert into `t2` select * from `t1`;

INSERT INTO `t2`  (

with recursive series as (

select 1 as id,LEFT(MD5(RAND()), 36) as r1 union all

select id +1 as id, LEFT(MD5(RAND()), 36) as r1  from series

where id < 50000)

select r1 from series);

insert into `t1` select * from `t2`;

INSERT INTO `t1`  (

with recursive series as (

select 1 as id,LEFT(MD5(RAND()), 36) as r1 union all

select id +1 as id, LEFT(MD5(RAND()), 36) as r1  from series

where id < 5000)

select r1 from series);

  select count(id) from t1 where id in (select id from t2);

  select count(id) from t2 where id in (select id from t1);

MariaDB [d1]>   select count(id) from t2 where id in (select id from t1);

+-----------+

| count(id) |

+-----------+

|    150000 |

+-----------+

1 row in set (0.299 sec)

MariaDB [d1]>   select count(id) from t2 where id in (select id from t1);

+-----------+

| count(id) |

+-----------+

|     33616 |

+-----------+

1 row in set (0.290 sec)