Single Application Mode under macOS Catalina?

Hi all,

First time here. I tried searching. But, didn't find anything that looked like a resolution to my problem so am asking.

The owner of the company I work for used an application called Liteswitch X to create a "Single Application Mode" in macOS. Unfortunately, that application is now abandonware because it is 32bit, and the developer has said it would take too much work to port it to 64bit.

As such, the owner is asking me to come up with a way to resurrect this mode because it helps his productivity.

I had created a shell script on my macOS Mojave, which accomplished what he wants to do. But, when he tried implementing it under macOS Catalina it had no effect. I figure it must have something to day with the ramped up security that Apple added with the latest O/S.

FWIW: Here's the shell script that worked:

defaults write single-app -bool TRUE
killall Dock

Anybody done that?

Thanks in advance,


I see that there is a "Hide All Windows" macros within Keyboard Maestro, which was doing what I wanted. HOWEVER, I managed to create a macro that closed all the app windows I wanted to close as well as the current one I wanted.

As a result, I'd start a program (example: Mail), it would pop open, and then immediately minimize to the Dock. Nothing would stay open; including the Keyboard Maestro app itself.

I was able to get by that hump by closing the engine, and then deactivating the macro.

But, at least the theory is there. I just need to know how to be able to keep the app window open that I want, while the other ones minimize.