I'm facing the same problem as addressed in this discussion: After switching from legacy QLGenerators to Preview extensions on macOS I cannot debug the extensions' code in Xcode, anymore:
I launch the app with the embedded appex from Xcode in debug mode. When trying to attach to the appex process the following error is reported:
Code: 6
Failure Reason: Ensure “AppName Preview” is not already running, and matthias has permission to debug it.
User Info: {...
}
System Information
macOS Version 15.4.1 (Build 24E263)
Xcode 16.3 (23785) (Build 16E140)
Timestamp: 2025-05-12T14:07:14+02:00
I'm using a standard user account (no admin) and might miss some obvious steps. Can someone detail the steps to debug a Preview (or Thumbnail) extension with Xcode 16? For legacy Quick Look plugins I was using "qlmanage", but that's not working on extensions.
All the best, Matthias
P.S.: Pardon me re-posting my reply as a separate thread, to increase visibility, but I'm quite desperate and couldn't find any solution on the web...
