10.14 passing bookmark to Helper App - Non Sandboxed

I have a Developer ID app which is not sandboxed. It has small helper apps stored within. The purpose of the app is to process Photos. Under 10.14, the user can drag & drop photos from Photos.app to my app, and everything works as expected (the user is prompted to approve access to Photos, and if they agree, then my main app can read the photo data).


However, the problem is when I try to pass a URL to the helper app to do some processing. The helper app does not trigger the UI and does not show up in System Preferences / Security. Instead, it is simply blocked from reading the file.


If this were a Sandboxed app, I've been told that there's a solution:

  1. in the parent app, create a non-security security-scoped bookmark
  2. pass the bookmark to the helper app
  3. the helper app must also be sandboxed and have com.apple.security.inherit set.


But my app is Not sandboxed, and I don't think that sandboxing is feasible.


What can I do?