MariaDB 10.3.32 and Jira 8.20 - possible? I can't get the set-up right

I have tried everything, I just can't get a Jira 8.20.6 set up together with MariaDB. Maybe someone can give me a tip on how to do it after all?

I am still at the beginning of the installation. Jira 8.20.6 is installed on Ubuntu 20.04. I started it for the first time via the web interface and then got as far as configuring the database interface. MariaDB with version 10.3.32 is installed and also working, I was able to check this via the console and via phpMyAdmin. For Jira I have created a separate database and a separate user and the access works in principle. When I then try to configure the database, I can only select MySQL5.7 or MySQL8 in Jira. Neither works.

I have of course downloaded both MySQL JDBC drivers/database connections (mysql-connector-java-5.1.49 and mysql-connector-java-8.0.28) and put them in Jira's lib directory.

When selecting 5.7 I get the error message "Connection failed: MySQL less than MySQL 5.7 is not supported in this configuration. Please consider using MySQL 5.6 database type."

When selecting MySQL8 I get the error message "The database type in your dbconfig.xml is set up to MySQL 8.0 and your MySQL version is different." However, before that it reports "Attempting to connect to localhost:3306/jiradb Connection successful!" and also writes the dbconfig.xml.

I also tried installing the MariaDB driver (mariadb-java-client-2.3.0.jar) by hand and adding it to the dbconfig.xml, but then Jira starts with a database error on boot, it can't access the database.

Is there somebody who can give me a hint how to configure Jira with MariaDB? Or can somebody send me an example dbconfig.xml that I could use?

I would be very happy about any feedback! Thank you!

Greetings, Peter