One of the great strengths of developing apps for macOS is the ability to communicate with the entire Mac and all it's installed applications.
Circular Software desktop apps all run alongside Adobe InDesign but also may need to talk to the Finder, Safari, Adobe Photoshop or Acrobat and lots of other helper applications to run effectively.
In later versions of macOS (from 2018's macOS 10.14 Mojave and onwards) Apple makes the user aware, and asks their permission, when first running any newly installed application.
When you first launch your Circular Software application will need to be grant permission to talk to and control other applications by clicking OK to any alerts like this.
It is important that you do allow these communications if you want to continue to use our software. If you do not allow them, processes will be disrupted and you may see alerts such as:
If you have accidentally disallowed events and want to reset them, check the security and privacy tab of the Mac System Preferences.
Pro tip: For experienced macOS users, you can also reset these choices with a terminal command. Once reset, the user is once again asked to allow the control of other applications on launch.
$ tccutil reset AppleEvents
More info here.