Thread hang in 'starting' state on FLUSH TABLES and shutdown hang, where the original table is a LOCKED GTT

CREATE GLOBAL TEMPORARY TABLE t (x INT KEY) ON COMMIT PRESERVE ROWS;

SELECT * FROM t;

LOCK TABLE t WRITE;

FLUSH TABLE t;

12.0.1-opt>SHOW PROCESSLIST;

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

| Id | User | Host      | db   | Command | Time | State    | Info             | Progress |

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

|  4 | root | localhost | test | Query   | 1372 | starting | FLUSH TABLE t    |    0.000 |

|  5 | root | localhost | test | Query   |    0 | starting | SHOW PROCESSLIST |    0.000 |

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

2 rows in set (0.000 sec)