What is this symbol and why is it not used always?

This symbol is quite possibly the coolest FL image I’ve seen. Is it new?

I’ve been playing for about two years and this is the first time I’ve seen it.

That was definitely not the icon back when I did that story. I’m pretty sure it was just the glimpse of something larger icon.
Although, I was also very sure that I sold my copy of the…thingy from the face-tailor story (can’t remember what it’s called)… for 12 echoes, which I am very wrong about, so I may be mistaken.
In any case that is pretty cool.