BUG #16633: Foreign data wrapper mysql-fdw issue

The following bug has been logged on the website:

Bug reference: 16633
Logged by: Emmanuel O
Email address: emmanuel(dot)ona(at)seetickets(dot)fr
PostgreSQL version: 11.9
Operating system: Debian GNU/Linux 10 (buster)
Description:

Hi

i'm facing an issue with PG11 using the mysql_fdw with a remote Mariadb
Column Store database (10.2.10-MariaDB-log Columnstore 1.1.2-1)
Requesting a simple select on a foreign table the error message is

postgres=# select * from mysql_foreign_table1 limit 5;
ERROR: failed to execute the MySQL query:
Commands out of sync; you can't run this command now

the select is still requesting on the MariaCS server until the PG session is
closed

i'm in trouble to see that this select runs well with this environment:
PG11/debian Stretch

but not with:
PG11/debian Buster
PG12/debian Buster

A Mysql client on the PG server requests with no issues in all cases

Thanks a lot

Emmanuel