Is debugging with App Data broken?

Trying to use App Data on Xcode 16.2, and failing

I'm running the app with the debugger. When I run the app, I need to do a handful of things, which affects my app's cache files, and UserDefaults. What I'd like to do is store all of these settings, then have them loaded in when the app launches, so I don't need to do same, tedious work of changing settings by hand in the UI.

So, I discovered that I can provide an xcappdata directory in the Run options. This seems like exactly what I'm looking for. But I can't seem to get it to work. Like, when the app runs, it looks like none of those settings are brought in.

I ran the app on a device, and pulled down the application data, and then put that in the project. And you can see in the screenshot, that the value is set.

So, either I'm missing something (which is totally possible) or this feature is broken. Documentation on this is not great, so maybe I'm doing something wrong. If the feature is known to be broken, I'll give up on this. But if it should work, it would be great to get some tips here.

Is debugging with App Data broken?
 
 
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