What is this symbol, I can't figure out what add-on it is

[Fergrim]

!#? is what's on the button and when pressed it simply says "Enter multiplier" and "Multiplier decrease per minute" with no title and no indication of what it does.

 

I'm so confused as to why there wouldn't even be as much as a title included. Does anyone know what it is?

[Jas0n]

Can you provide a screenshot?

[Booots]

I'm pretty sure that's DangIt. I'm not sure what the multiplier stuff does, though.

[Fergrim]

I can get a screenshot if necessary but the symbol it literally a white square with !#? written on it.

 

And okay I do have dangit

[Zhetaan]

7 hours ago, Fergrim said:

And okay I do have dangit

@Booots is right.  You'll find it in GameData/Dangit/Textures as appBtn.png.  I can't tell you what the multiplier does; I'll have to go digging for that.