Minecraft Does anybody have this?

Read the title, I meant if anyone had these before.
And no, it doesn't need a restart. It disappears if I pressed one of the buttons, but it is a rare screen though.
It looked cool if you have it, it has this fade effect. I took the screenshot as I saw it in a second, I guess I took it way too early. xD

 

Never had it on my Mac, but I've had one similar on my laptop, certainly not as dark as that.
It was about 25% brighter, but it was still pretty dark. :P

 

It could be placed on purpose by Mojang, like @Dirtbikes95 said.

 

I personally haven't seen it, but the I've seen the message a bunch of times. I think that's what makes it rare; it must have that message and probably be one in some random number of start ups.