UPDATED 5:39 p.m. ET: Seth Hirch's "Say Goodbye" featuring Mac Miller has been removed from AudioMack. The song will not hit digital streaming platforms as originally announced.

Read the original story below.

In the year before his tragic death, Mac Miller had recorded a track featuring up-and-coming rapper Seth Hirsch. The song, called "Say Goodbye," was produced by Mac's previous collaborator Nottz and remained in the vault throughout 2018. It was originally intended to land on Hirsch's upcoming debut album, but just five months after Miller's untimely death, the rapper decided to release the effort as a tribute.

"The song’s about toxic relationships, and dealing with someone who's shitty towards [you], sucks up all your energy, and keeps taking advantage of your time and emotions," Hirsch said about the song. "But after Mac passed away, I realized this song was about a lot more than that. It's really about struggling to say goodbye to our personal demons and the chains they put on us. ... This song is such a window into Mac Miller's soul and what he was going through."

"Say Goodbye" will officially hit major streaming services Thursday but can be heard via Audiomack below. Proceeds from the record merch will also benefit victims of the shooting rampage at Tree of Life synagogue, which is located in Miller's hometown of Pittsburgh.

Miller was found dead Sept. 7, 2018, inside his Studio City home. The Los Angeles County coroner's officer determined the rapper had died from an accidental overdose of fentanyl, alcohol, and cocaine. Miller's last studio album, 2018's Swimming, was nominated for Best Rap Album at the 61st annual Grammy Awards. The honor ultimately went to Cardi B (Invasion of Privacy), but she later announced she was sharing the award with the late artist.