Note that this process will require you to put your Steam credentials into the third-party software, DepotDownloader.
Step 2: Download and extract the latest stable release of DepotDownloader This is my process for this specific game but, as far as I know, it can be applied to any Steam game. In order to regain compatibility I needed to rollback or downgrade my Windows version so that it would be on the same, older version as my friends on macOS. This update had the unfortunate side effect of breaking compatibility between the Windows and macOS versions of the game, meaning that when the two versions tried to join an online game it would spit out a “Version Mismatch Error”.
Yesterday, Sid Meier’s Civilization VI got a new update for the New Frontier Pass.
