Migrate from postgresql to mysql

I know there is a guide for how to convert from MySQL to PostgreSQL, but is there any information about the opposite?

I have few applications that require MySQL and I would like to move Gitlab to MySQL in order to only maintain one database server.

There is an old guide available that says it’s just straightforward backup-and-restore, but when I take a look at the MySQL to PostgreSQL guide I’m pretty sure it’s outdated, isn’t it?