Debugging error when enabling Event Scheduler

Question

I am trying to set up IDE (PHPStorm) to use schema Introspection. To do this I need to enable Event Scheduler. I used this script :

    SET GLOBAL event_scheduler = ON;

Unfortunately I am getting an error :

Event Scheduler: An error occurred when initializing system tables. Disabling the Event Scheduler.

I am not sure how to debug this. The error message contains too little information for my knowledge. What cloud be the reason for failed initialization of system tables? I am using 10.4.8-MariaDB

Answer 1

Run mysql_upgrade a second time.

https://jira.mariadb.org/browse/MDEV-18788