not real haha. Aside from "luck be in the air tonight" not being a phrase I've ever heard anyone say in any context, it doesn't make sense as the solution because the "i" in "in" and also "tonight" is already revealed yet it isn't for the word "air" (must admit I didn't notice this, until I saw it pointed out).
What are you talking about? The 'i' in both 'air' and 'tonight' is not revealed. Just like it's still hidden in 'air'. Or am I misunderstood something...?
EDIT: Ah, you're referring to the Snopes article you linked. I get it, but the rest of us are just commenting on the post and image here.
If you follow their link, you'll see the original had the issue they describe. The one posted here seems to have been (further) photoshopped to solve the issue of the original.
Oh snap haha. Yeh I'm a dumbass. Nevertheless, it is definitely fake, which is something you can really determine just from context given the relative unlikelyness of this being missed and the fact that, "luck be in the air tonight" is not a phrase, but it's good to know that this even exists in multiple forms out there meaning it's definitely been manipulted.
It's a portmanteau of the lyrics "Luck be a lady tonight" and "I can feel it calling in the air tonight" which is why it feels just familiar enough to seem real, but not actually.
This would be in the category "before and after" where the middle of the puzzle ends one saying and begins another. The solve would be "tuck me in" along with "in the air tonight".