I am using osclass 3.9 and Mariadb 10.1 but I am getting notice in cpanel to upgrade to Mariadb 10.2 or 10.3 but when I go to upgrade I get the following message. I want to know if 3.9 will work before upgrading to Mariadb 10.3  I cannot go back to 10.1 if there are any problems.
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Upgrade Warnings

Critical

MariaDB enables "strict mode" by default as of version 10.2. Strict mode controls how MariaDB and MySQL handle invalid or missing values in data-change statements such as INSERT or UPDATE. Applications not built with strict mode enabled may cause undesired behavior; please verify applications using MariaDB are compatible before upgrading. More information about strict mode is available here .

Normal

The selected MariaDB version (10.3) is more than one generation newer than the currently installed version. The upgrade process will iterate over each intervening version to ensure tables are upgraded appropriately.