In the credits to Spider-Man: Into the Spider-Verse, it is listed that Post Malone voice acted one of the Brooklyn bystanders. My question though is, which one?
No official words I can get about it but IMDb claims Malone said this line:
Brooklyn Bystander : [looking at a glitched stoplight] I think it's a Banksy.
Going through official script, only one Brooklynite have a speaking line and it's same as IMDb and you yourself said he was credited as Brooklyn bystanders.
ET Online confirms it:
“Post Malone gets a pretty big laugh in the movie,” Lord said of the GRAMMY-nominated rapper, who contributed the song "Sunflower" to the Spider-Verse soundtrack and has a cameo as a "Banksy enthusiast" Brooklyn bystander.