Remeber kids: The logo is a unicode symbol in a font that is licensed as public domain. And you can’t copyright or trademark a single letter without stylization, colors, etc.

Here is the font: https://dejavu-fonts.github.io/ (the sans version)

The symbol: 𝕏

Have fun.

I think xxx would fit well too :p

But i have a questin: what does it mean? I am not informed enough