Theming your Linux desktop to look totally different. See r/unixporn

I'm guessing it's a reference to the fairly racist label of a "ricer" or "rice rocket" for modified Japanese sports cars :-/

Nothing racist about it, it's derived from the practice of putting cheap sake in in the hope that it would work like MW50 injection (it doesn't).

This is definitely a racist term that was targetting modified japanese cars. It should have been forgotten long ago instead of importing it in the computer world where it doesn't even make sense.