Can upgrade from MariaDB 5.5 to MariaDB 10.3 directly? We have a database running in MariaDB 5.5.60 and we want to upgrade it to the last 10.3.7 version.

However I'm looking at MariaDB knowledge base ( https://mariadb.com/kb/en/library/upgrading/ ) and I'm not sure if we can perform a direct in-place upgrade from 5.5 to 10.3, or we should perform a "step by step" upgrade (5.5 > 10.0 > 10.1 > 10.2 > 10.3 ). 

All the documentation I see in the oficial MariaDB knowledge base seems to suggest to do a in-place step by step upgrade (furthermore, looks like a logical upgrade with mysqldump cannot be permormed from 10.2 to 10.3), however I've seen some other examples in blogs where a direct in-place upgrade from 5.5 to 10.2 seems possible ( http://www.linuxtopic.com/2017/10/upgrade-mariadb-5.2-to-10.2.html ).

Any help?
Regards
The whole jump it is possible (depends on your data structure) but is not recommended and based on official documentation is not supported.

The best option is to perform and step-by-step IN-PLACE upgrade so you will only do a mysqldump before start to backup everything then just install every version and run mysql_upgrade then continue with next version and so on.