galera.galera_unicode_identifiers MTR failed: InnoDB: innodb_fatal_semaphore_wait_threshold was exceeded for dict_sys.mutex

galera.galera_unicode_identifiers 'innodb' w1 [ fail ]

        Test ended at 2021-08-29 05:59:09

CURRENT_TEST: galera.galera_unicode_identifiers

mysqltest: In included file "./include/wait_condition.inc": 

included from /usr/share/mysql/mysql-test/suite/galera/t/galera_unicode_identifiers.test at line 57:

At line 54: query 'let $success= `$wait_condition`' failed with wrong errno <Unknown> (2013): 'Lost connection to server during query', instead of  (0)...

The result from queries just before the failure was:

< snip >