Beau mail d& 39

I think you meant to type "beau mail" which is French for "beautiful mail"!

However, I'm assuming you might be referring to the phrase "beau mail" as a common internet slang term, which is short for "beau message" or "beautiful message". In this context, "beau mail" is often used to express excitement or admiration for a particularly well-written or thoughtful message, usually in the context of online dating or social media.

Am I correct?