During the import of databases and all tables that use Aria engine, from MariaDB 10.6.X to MariaDB 10.5.16, I got the below warning

ERROR 1071 (42000) at line 494: Specified key was too long; max key length is 2000 bytes

So, I have changed the engine of all tables to InnoDB and repeat the import, all tables have been imported successfully, but when I tried to drop some of these databases I got the below warnings:

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

| Level | Code | Message                                                      |

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

| Error | 1728 | Cannot load from mysql.proc. The table is probably corrupted |

| Error | 1545 | Failed to open mysql.event                                   |

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

Also, I tried to run mysql_upgrade --force and the same error appeared.
Furthermore, I removed all files that under /var/lib/mysql and run mariadb-install-db, then imported the databases, and it's completed successfully, but also when I drop any database I get the same previous warnings.