Possible Bug with setting Preference Variables

That's because it is. I didn't just say it, I tested it as you can see from my GIF.
I've done what you asked thousands of times by now. Since no changes have been made to KM in months, I can virtually guarantee you that KM is working properly.

Another classic response is do the obvious, standard troubleshooting:

  1. Restart KM Editor
  2. Restart KM Engine
  3. Restart your Mac

Just for the record, what ver of KM and macOS are you running?
I'm running Keyboard Maestro 7.3.1 (7.3.1) on macOS 10.11.6.

If you have a macro that is not working properly, please post it, and state exactly what is wrong.

See