Error with finding files in bundle on OS-X 11 (Big Sur)

[Chris Barker - NOAA Federal]

I've just got a new mac with OS-X 11.6 (still Intel).

But when I try to run a PyInstaller built application, I get this error:

No document available for {'mime': 'application/x-maproom-project-zip', 'loader': <maproom.loaders.project.ZipProjectLoader object at 0x7f9669ce6e10>, 'uri': 'template://default_project.maproom'}

And the app won't start.

This has worked just fine on numerous previous OS-X versions.

I'm not sure what version of PyInstaller was used, but it was built in May 2019.

I have the source code, but the developer that built it is no longer with us, so it'll take me a bit to get up to speed, and I don't even know where to start! Is this a PyInstaller issue? or a code issue, or ???

Hints:

The application is called MapRoom (maproom) it works with "projects" that are essentially a zip file with all the info required in it.

On startup, it tries to load an empty default project: "default_project.maproom"

Looking in the app bundle, the template is in:

MapRoom.app/Contents/Resources/maproom/templates/default_project.maproom

so I think what's changed is the root for the uri it's using:

 'uri': 'template://default_project.maproom'

As the bundle is exactly the same the newer version of the OS must be doing something different with the current working dir, or ???

Another maybe relevant point: this is a wxPython project, so may be using some wx magic to find files in the bundle ???

Thanks for any hints,

-CHB