Why these queries cause dirty read in REPEATABLE-READ Isolation Level

Question

these queries causes DIRTY READ. I thought that REPEATABLE-READ guarantees that the second select statement in trx2 doesn't return anything. But, the statement returns the row that inserted by trx1 even though the trx2 not committed yet

trx1:

begin;


select * from tableA A where A.id = 1 for update;

select * from tableB B where B.id =2  and B.col_1 = 3;

insert into tableB (id, col_1, created_at) values (2, 3, now());

update tableA set col_2 = 2 where id = 1;


commit;

trx2:

begin;

//waiting until trx1 is committed
select * from tableA A where A.id = 1 for update;  

select * from tableB B where B.id =2  and B.col_1 = 3;


commit;

I expected the second selection in trx2 to return nothing.

to the additional... each transactions that be added the another select statement just next begin doesn't show any DIRTY READ

trx1:

begin;

select * from tableC C where C.id = 3;

select * from tableA A where A.id = 1 for update;

select * from tableB B where B.id =2  and B.col_1 = 3;

insert into tableB (id, col_1, created_at) values (2, 3, now());

update tableA set col_2 = 2 where id = 1;


commit;

trx2:

begin;

select * from tableC C where C.id = 3;

//waiting until trx1 is committed
select * from tableA A where A.id = 1 for update;  

select * from tableB B where B.id =2  and B.col_1 = 3;


commit;