No, MariaDB is a fork and has meaningful functionality differences from MySQL. They've been diverging for over a decade and aren't drop-in replacements for each

No, MariaDB is a fork and has meaningful functionality differences from MySQL. They've been diverging for over a decade and aren't drop-in replacements for each other. Meanwhile Percona Server is a drop-in replacement for MySQL, essentially it's a large patch-set on top of MySQL rather than a fork. Percona Server releases line up with MySQL releases and versioning. Whenever Percona Server features break binary compatibility, it's explicitly noted in their manual, and not enabled by default.