Just a few days ago, Aspyr released an update to their macOS port of SimCity 4 Deluxe to add native support for Apple Silicon processors–a move that will allow their port to continue to run on that platform even after Apple’s inevitable removal of the Rosetta 2 compatibility layer in the not-too-distant future.
For those who haven’t followed the saga of all the various digital editions of SimCity 4 that are available now, the Aspyr macOS port is distributed via two different platforms: Steam and Apple’s own App Store. And there are some very important differences between the editions offered via each platform, namely in terms of how they handle plugins and mods. The Steam version works very similarly to the Windows version, in that the Plugins folder is stashed within the user’s Documents folder.
However, due to Apple’s packaging requirements, the App Store does not use an external Plugins folder. Instead, the plugins are to be placed directly inside the .app container–specifically, per Aspyr, ~/Library/Containers/com.aspyr.simcity4.appstore/Data/Documents/SimCity 4. Since the .app file is what is being updated here, this means that updating one’s App Store version of the game will delete all one’s plugins. This sad fate happened to /u/SydneyEditor over on Reddit, as detailed here.
In order to avoid this, App Store users should backup the plugins within the .app before installing the update, by copying them to an external location.
-Tarkus