It's important to note that Chekhov's Gun was not originally about foreshadowing, but a piece of advice to playwrights about how every element in a play should have narrative relevance. The corollary to Chekhov's Gun is that if a gun mounted on the wall in act 1 is never used at all in the entirety of the play, then it should be omitted from the play entirely.
also very true
Very funny example of writing advice that is very specific to its medium getting overapplied outside its scope. Can you imagine how awful set design would be if people tried to apply this to movies. 60 minute post credits scene in the Matrix where Neo has to fire every gun that appears in the "lots of guns" scene





















