In case you are not aware, there will be a whole lot of Mac apps that will stop working if you upgrade to macOS Catalina later this year. Now it seems that Apple has actually included a specific list of a whole bunch of them in beta for the new operating system.
As reported on his blog, The Tape Drive, iOS developer Steve Moser recently discovered a hidden file in the latest macOS Catalina beta called IncompatibleAppsList.bundle that explicitly lists 235 apps that are incompatible with Catalina, together with text describing why they are incompatible and in some cases offer recommendations.
As Moser notes, the list is designed to be used by the Catalina installation process so that apps with known incompatibilities can be flagged during an upgrade from an earlier version of macOS. In fact, many of the apps are just older versions that have been updated for a long time ̵
The bundle also includes strings intended to advise users about the incompatibility, probably presented during the upgrade process if any of the infringing apps are detected in a user's system. Many simply say something like "this version of (app) is not compatible with this version of macOS", while others refer users to another app. For example, if TextWrangler is detected, macOS will tell the user that it has been "end of lifed "and recommends that they update to the company's replacement app, BBEdit.
Why Is This Happening?
Apple has been working for several years with the transition to 64-bit apps, since these are not only more efficient for modern Macs, but by eliminating support for 32-bit apps, Apple can also clean up and simplify a lot of the code under the hood of macOS.
Writing has been on the wall for most developers for at least a couple of years, especially after Apple made the first such move with iOS when it dropped support for 32-bit apps in iOS 11 back in 2017. Of course since it wouldn't being equally obvious to end users, with the release of macOS Mojave last year, Apple began alerting users that their apps would be incompatible with "future versions of macOS" and urging them to update their apps or seek replacements.  What should I do about it? [1 9659006] We gave some instructions and advice last month on how to find out if your apps will still work in macOS Catalina, which offers a way to tempt out every app already on your system that won't be compatible with it new operating system.
In addition, Moser has also benefited from sharing the IncompatibleAppsList file on GIST, and while in the original PLIST format, you can still open it in a text editor and scan or search through it to see if any of your favorite apps is on the list.
In either case, if you discover an app that will not be compatible with macOS Catalina, you basically have three options:
- Check to see if a free 64-bit update is available. This is clearly the best and most seamless option, and if the app offers its own software update process, or if it came from the Mac App Store, you should probably get the necessary updates automatically just by looking for them.
- Check with the developer to see if a newer paid version of the app includes 64-bit support. If the app has had a major update over the last couple of years, there is a good chance that the developer will not offer 64-bit support in the older versions of their app, which have been effectively run. The downside is that this means you have to pay for an update if you want to continue using that app and will run macOS Catalina.
- Check with – or request – the developer to see if they have any plans to add 64-bit support to the version of the app you're using. Some developers may be willing to release small updates to older versions of their apps just as a goodwill gesture to their customers.
- Find an alternative app that will work for you. If you run an older app that is no longer in active development, chances are you won't find a 64-bit update for it. Although transitioning to a new app can be difficult, there are many other benefits to switching to an app that is actively maintained by the developer, rather than continuing to run one that has been abandoned.
- Do not upgrade to macOS Catalina. While not a long-term solution, you can always stick to macOS Mojave if you have apps that are critical to your non-64-bit workflow and can't find viable options. There is probably nothing that forces you to upgrade to the latest version of macOS.
- Run Mojave on a virtual machine. If you have a non-64-bit app that won't be 64-bit, and you certainly can't live without it, but you still want to upgrade to macOS Catalina, use a virtualization app like VMWare Fusion or Parallels give you the best of both worlds. You will need extra disk space and maybe a little more RAM than usual to support another virtual machine, but doing so will allow you to run your very own macOS Mojave system in macOS Catalina, though you will of course want VMWare and Parallels itself is updated to support Catalina as well.