In my experience, aText has been the best text expansion software (multiple reasons, including flexibility, fast search with very large library, and reliably working with Citrix-based medical record systems). It’s also only $5!
At some point, Keyboard Maestro became unable to detect that aText was the foremost app–figured out this was because it was acting as a “pop-up” service rather than application, and Peter was unable to do anything about it…
HOWEVER, I recently figured out that it was something about aText had changed! I had unchecked “Show aText con in Dock”…and that is what made the system not see it as an application.
SO, if you CHECK “Show aText icon in Dock,” then aText will act like a normal app, and Keyboard Maestro can detect this and behave accordingly! Other bonuses of this: you can Cmd+Tab to it, and you can see its menu items on the menu bar!