Can also be usefull in dev env
Maybe add a more generic sentence for both env?

I don't really know why you would use it in dev env, but I may be wrong. 😥
What can be your use case for example?

Because you may not have install any mailer soft
And want to check the rendered email

The idea is to not document as « only for test env » and let developers choose, of course test env is the best usage but other can be usefull also :)

Hum that's right, I've updated the documentation :)

The code-PR is closed. Can we close here @Kocal ?

Ah yes we can close it, I forgot about it.