could either mean short for "hey you sit down in front" (as if the person was blocking a view) or it could mean short for "hey look i am down in front!" proclaiming seated-superiority....
in futurama season two episode twelve entitled "raging bender", all the gang went down to the theatre and the professor shouted: "down in front!"

i was at a ball game and some guy shouted "hey! down in front"

for the love of bhudda, would someone give a clearer definition of down in front than this jerk?
by he who stands there September 21, 2008
To a female, seated, who is wearing a skirt or dress, and whose legs are spread showing her panties in front, telling her to adjust herself clothes.
Yo Emma! Down in front! Everyone can see yo personal stains!
by rusty444 May 28, 2021