"The four episodes of “The Hateful Eight: Extended Edition” are titled
“Last Stage to Red Rock” (50 minutes),
“Minnie’s Haberdashery” (51 minutes),
“Domergue’s Got A Secret” (53 minutes),
and “The Last Chapter” (56 minutes). "
edit: when all additional episode opening/closing credits, along with new episode titles, are removed,
it gets to 3hrs 6 min movie.