Yes, exactly.
People complained and they moved the folder on osx and Windows but not Linux apparently.
It appears to create the folder even when disabled. This behavior apparently started around java 1.8u60. It persists in 1.8u112.

Because this folder is recognizable by its funny name, another solution would be to post a request to MariaDB to ignore it, in particular when doing a mysqldump.

It shows up in show databases as well.
You might try passing the parameter that specifies the property file on jni startup with a blank parameter. Specifics are listed in the file itself. This may, or may not, prevent the folder from being created.

Possible but as the Oracle documentation says that usage tracker is disabled by default this is probably because on Linux it creates the folder unconditionally.

However, I still think that it is a flow in MariaDB to regard any sub folder of the data directory as a database. There should be a way to eliminate not real ones, for instance by adding a specific file in the folder when the CREATE DATABASE is executed.

Meanwhile, if it is possible to manually remove this folder, a workaround could be to do it before executing a mysqldump, which by the way is probably not executed so frequently.

Sort of agree on " I still think that it is a flaw in MariaDB to regard any sub folder of the data directory as a database." but also think that it would not be an issue if MariaDB default install didn't use the Linux home folder as its data directory. It could use a subdir of its home dir like ~/data or ~/mysqldata or maybe use /var/lib/mysqldata ... not sure. But using the home directory itself seems like a bad default install practice.

So far, the work around that seems to be not a kludge for me is simply to change the location of the mysql data dir.