Ya it's default XF. XF took a universal approach with the CSS this time around. Everything uses global classes for the most part so they avoid specific items a lot more this time around. We may add a property in for it though to help with styling.Thanks
It's a XF thing not a PixelExit thing right? Isn't it weird to have a class like that (a major page building block) with no style property?
I've added it in extra.less for now.