Unfortunately, Apple seems to have broken utilities like Keyboard Maestro in Mojave, and if you rely on macros, it's a very bad thing. I upgraded to Mojave late last week (although it's still not theoretically a GM) and found that although some actions still worked without any problems like app launch by others (especially my universal Emacs key piano equivalents).
I found this thread on the issue on a Keyboard Maestro forum. The hints on that thread helped me to work out this solution to the Mojave problem. Note that you may have to repeat the steps after restarting your Mac.
/ Programs / Keyboard Maestro.app/Contents/MacOS/Keyboard Maestro Engine.appto /Applications.
- In Terminal, Kill Keyboard Maestro and Engine Processes.
- Open System Preferences> Security & Privacy> Accessibility. Give privileges to both apps: Maestro and the Copied Engine. (I have also granted Finder and Safari privileges, which probably were not required.)
- Start Engine from / Applications. Check the process list for
/ Programs / Keyboard Maestro Engine.app/Contents/MacOS/Keyboard Maestro Engineand test your macros. You can have many types of macros and you want to beat as many pieces of the operating system as possible when making sure that each type of macro is properly launched and executed.