Piss on your chips means: It’s okay to eat your chips. This applies to an internet forum in which impostering is common. The forumer pretending to be someone else forgets their username and creates a new post. Also see: Pissage, Chips, POYC. (in Community Dictionary, added by Nazario Aguilar)

What else does Piss on your chips mean?

  • This expression should be understood to mean that you really make something worse for yourself than someone else by doing an uncalled for or stupid thing. It is self-inflicted, so it has a different meaning than “piss on my bonfire” and “rain on my parade”, which are used to refer to spoiling or placing a damper on someone else’s work. This expression comes from an English scenario where a man buys take-out chips and french fries after a night of drinking. The drunken man realizes he needs to take a swig on his way back. He finds somewhere quiet and places his chips there while he relieves. He then accidently licked his chips and deprived himself of his meal due to his stupidity and carelessness. This expression applies especially to celebrities who have suffered a career-threatening personal injury. (in Community Dictionary, added by Gavin Dawson)
  • Put a damper on it. (in Community Dictionary, added by Olga Martínez)