OG Link https://sonic3air.org/
Windows ver https://sonic3air.org/downloadgame_win2.php
Minor https://sonic3air.org/downloadgame_win.php
Preview ver https://sonic3air.org/downloadpreview_win.php
Linux ver https://sonic3air.org/downloadgame_linux2.php
Linux minor ver https://sonic3air.org/downloadgame_linux.php
Linux preview ver https://sonic3air.org/downloadpreview_linux.php
Mac ver https://projects.sappharad.com/s3air_mac/sonic3air_mac_210928.dmg
Before downloading, please make sure you have the Steam version of Sonic 3 & Knuckles  installed Windows And Linux Users
The macOS port by Sappharad.
Before downloading, please make sure you have the Steam version of Sonic 3 & Knuckles  installed Mac Users
View changelog
https://sonic3air.org/changelog.txt
Linux view changelog ver
https://sonic3air.org/changelog.txt
Mac view changelog
https://projects.sappharad.com/s3air_mac/changelog_mac.txt