Steam is a popular video game distribution platform for both Macs and PCs. It offers its own app store, where you can buy and download games to play on your computer. On the Mac, Steam gives you access to a much wider variety of games than you can buy directly from publishers, or from the Mac App Store alone.
If you are running Steam on an old Mac — one running a version of macOS prior to macOS Catalina (10.15)
— an upcoming change to the Steam app will affect how you can use it. On February 15, 2024, Steam stopped supporting Macs running macOS Mojave (10.14) and macOS High Sierra (10.13). Steam says that only 2% of Macs using the Steam app run these operating systems, but it’s quite possible that you have an old Mac running one of these versions of macOS — perhaps even specifically to play old games that haven’t yet been updated to run on newer Macs.
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The main reason for this change is the support for 32-bit apps, which Apple dropped in macOS Catalina. Steam says that “many developers have not updated their games to support 64-bit executables;” therefore the “Steam store will stop considering games that offer only 32-bit macOS binaries to be Mac compatible at the end of 2023.”
Another reason for the change is because “core features in Steam rely on an embedded version of Google Chrome, which no longer functions on older versions of macOS.” The company also points out that these older operating systems are not secure. “Apple ended security updates and technical support for macOS 10.13 in December 2020 and for macOS 10.14 in October 2021.”
So, this begs the question: If you have an old Mac running one of these versions of macOS, and 32-bit games you can’t play on a newer system, what can you do?
Starting February 15, you may no longer be able to update the Steam app or purchase any new games on an older Mac. But, assuming that you’ve previously downloaded Steam game titles onto an old Mac, you should be able to continue playing them.
It is true that there is a security risk when older Macs are connected to the internet. But if you have a Mac that is dedicated to just playing old games, and you don’t use it to browse the web or download anything else—particularly if you leave it disconnected from the network—this shouldn’t pose any problems. Steam does need to activate games the first time you play them, and it records statistics about your games. However, even if the Steam app no longer runs, you should be able to play your games in offline mode.
One exception is multi-player games; these may no longer work with the older Steam app. You may also no longer be able to access friends and chats via the Steam app, either.
You can launch games without going through the Steam app. Go to your Steam library, right-click on a game, and choose Manage > Browse Local Files.
This opens a folder where the game’s app is stored. You can launch a game by double-clicking the app, or its alias.
The top-level folder that contains all your Steam games is located in your user folder at /Library/Application Support/Steam/steamapps/common. You can browse this folder and open any apps from there.
Steam games don’t always include a double-clickable app icon or alias in the Finder. However, you may be able to create your own app icon to make it easier to launch the game.
The classic game Half-Life, for example, must be launched via a shell script. You can open the ~/Library/Application Support/Steam/steamapps/common/Half-Life folder, drag hl.sh onto a Terminal window, and press Return or Enter on your keyboard.
Want to make this process into an app? Open the Script Editor app (located in /Applications/Utilities) and paste the following text:
do shell script "~/Library/Application\\ Support/Steam/steamapps/common/Half-Life/hl.sh"
Then click on the File menu, Save…, choose Application from the “File Format:” menu, and Save the app wherever you like. The next time you want to run Half-Life, just double-click on your custom app.
Some games without an app icon in ~/Library/Application Support/Steam/steamapps/common may have a folder that contains a Contents folder. You can create an app for this as well.
One method is to do the same thing as above with the shell script example. Namely: open Script Editor, then type “do shell script” followed by a blank space. In the Finder, open the game’s Contents folder, then the MacOS folder; you’ll see a single file here. Drag that file onto the Script Editor window, and it will add the app’s folder path to the script. Enclose that path in quotation marks, and add \\ before any spaces in the app’s folder path. So, for example, if your game’s name were Coromon, the script would now look something like:
do shell script "~/Library/Application\\ Support/Steam/steamapps/common/Coromon/Contents/MacOS/Coromon"
Note that I’ve replaced /Users/myusername with ~ for convenience; the tilde character points to the current user’s home folder.
Just like the previous example, you can save this script as an Application wherever you like; then, simply double-click it the next time you want to play that game.
At some point, the Steam app may not run anymore, or may prevent you from logging in, on your old Mac. If you haven’t yet downloaded your classic games, there’s still a way to obtain them—as long as you have access to a newer Mac.
Download and install the Steam app onto a newer Mac, then run the app and sign into your account. Next, install your games onto the newer Mac; it will allow you to do so, even if the games aren’t compatible with that Mac’s hardware or macOS version.
Then you can open the ~/Library/Application Support/Steam/steamapps/common folder on the new Mac. You should find your freshly installed games there.
If your older Mac is on the same network, you can copy your games to your other Mac over a Wi-Fi or Ethernet connection. Otherwise, copy that folder’s contents onto an external hard drive or flash drive, and then plug the drive into your old Mac and copy the folders over. If necessary, you can create custom game launcher apps, as described earlier.
Although it’s now past the cut-off date of February 15, 2024, you might still be able to run the Steam app and launch games with it on an old Mac—for now. As soon as possible, download your Steam games onto your Mac with macOS Mojave or High Sierra, and launch all your games at least once to make sure that they’re activated and functional. Then you should still be able to continue playing older games either via the Steam app (as long as it’s still working) or by launching them directly in the Finder.
Just don’t expect to be able to play online multiplayer games forever. Eventually, developers may lock out old versions from participating in online play. And, of course, at some point there comes a time for every developer to decommission servers for old games.
Although it would be extremely difficult and impractical to make a comprehensive list of all Steam games that were designed to work on 32-bit Macs and never updated, here are a handful of notable titles we found.
A longer partial list is available from Mac Gamer HQ; it contains non-Steam titles, too, and is somewhat outdated. There’s also a Reddit post from a user who tested 450 games from their personal Steam library in 2020.
Are you aware of any other games that you think we should include in our list above? Leave a comment and let us know.
Looking for other cool things you can do with an older Mac? We’ve got you covered:
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