mysqldump --sys-triggers creates unloadable dump

CREATE TRIGGER trg1 AFTER STARTUP SET @x=1;

--exec $MYSQL_DUMP --sys-triggers test > $MYSQLTEST_VARDIR/tmp/dump.sql 

DROP TRIGGER trg1;

--exec $MYSQL test < $MYSQLTEST_VARDIR/tmp/dump.sql 

DROP TRIGGER trg1;

--remove_file $MYSQLTEST_VARDIR/tmp/dump.sql

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ALTER DATABASE `` CHARACTER SET utf8mb4 COLLATE utf8mb4_uca1400_ai_ci

--------------

ERROR 1102 (42000) at line 18: Incorrect database name ''

DELIMITER ;;

/*!50003 CREATE*/ /*!50017 DEFINER=`alice`@`localhost`*/ /*!50003 TRIGGER tr1 AFTER STARTUP SET @x=1 

*/;;

DELIMITER ;

/*!50003 SET sql_mode              = @saved_sql_mode */ ;

/*!50003 SET character_set_client  = @saved_cs_client */ ;

/*!50003 SET character_set_results = @saved_cs_results */ ;

/*!50003 SET collation_connection  = @saved_col_connection */ ;

mysqldump: Couldn't execute 'SHOW CREATE TRIGGER `tr2`': Trigger does not exist (1360)