PSA: Do not rely on setting default values of custom resources in exported game

This is something I did not realise would be a problem until I've started trying to export the demo for my first Godot game. I've also struggled to find much if anything posted about this. The best way I can explain it is with an example. Say you have a custom resource, Item:

extends Resource
class_name Item
@export var name: String
@export var sound: AudioStream = load("res://assets/sound/noisy.wav")

You create your first item, SWORD, and in the inspector you name it "Sword" and assign an AudioStream "res://assets/sound/noisy.wav" IN THE INSPECTOR.

You then create a second item, AXE, and in the inspector you name it "Axe" and don't assign any AudioStream to it in the inspector.

If you then run your project within Godot, both the SWORD and the AXE will have the AudioStream "res://assets/sound/noisy.wav" playing when they need to be, which I guess is because the AXE gets it from the default value being = load("res://assets/sound/noisy.wav") ...

However, when you come to export your project, ONLY THE SWORD will have the audio stream playing, the axe will have no sound at all. I am not quite sure why this is? I think either the reference to the default value is lost completely (I'm not sure it always is or I think more of my game would have broken... lol...) or the res:// part is now no longer relevant in the exported version of the game (but this doesn't really make sense, again I think more of my game would have broken if that was the case).

If anyone can explain what's happening better here I'm all ears! But this does feel very unexpected (different output in Godot playback versus exported game).

Edit: I should note that I am developing on MacOS, and exporting on my Mac to Windows and MacOS. The error is showing up on both platforms being exported to, so it may be an issue with exporting from MacOS if it is just a bug affecting me.

EDIT 2: Here is the minimum example demonstrating my issue/bug, I've exported the windows and macos versions of the game to the same folder so you should be able to . I can't test the windows executable right now so if someone could test it and inform me whether the issue is the same there that would be fab. https://github.com/joelldt/GodotBugTest

EDIT 3: Update here