Misleading error message due to FOREIGN KEY on RENAME TABLE

--source include/have_innodb.inc

CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB;

CREATE TABLE t2 (a INT PRIMARY KEY, CONSTRAINT t3_ibfk_1 FOREIGN KEY (a) REFERENCES t1(a)) ENGINE=InnoDB;

CREATE TABLE t2b (a INT PRIMARY KEY, FOREIGN KEY (a) REFERENCES t1(a)) ENGINE=InnoDB;

--error ER_TABLE_EXISTS_ERROR

RENAME TABLE t2b TO t3;

DROP TABLE t2b,t2,t1;

ERROR 42S01: Table './test/t3' already exists

2021-06-16 11:50:39 139702710404864 [ERROR] InnoDB: Possible reasons:

2021-06-16 11:50:39 139702710404864 [ERROR] InnoDB: (1) Table rename would cause two FOREIGN KEY constraints to have the same internal name in case-insensitive comparison.

2021-06-16 11:50:39 139702710404864 [ERROR] InnoDB: (2) Table `test`.`t3` exists in the InnoDB internal data dictionary though MySQL is trying to rename table `test`.`t2b` to it. Have you deleted the .frm file and not used DROP TABLE?

2021-06-16 11:50:39 139702710404864 [ERROR] InnoDB: If table `test`.`t3` is a temporary table #sql..., then it can be that there are still queries running on the table, and it will be dropped automatically when the queries end. You can drop the orphaned table inside InnoDB by creating an InnoDB table with the same name in another database and copying the .frm file to the current database. Then MySQL thinks the table exists, and DROP TABLE will succeed.