Hi Chris - very odd situation that's really got me stumped - my game plays fine when I play it in the editor, and the Inventory appears when it's supposed to. But when I build for WebGL and Mac (I haven't yet tried Windows, but I'm working on Mac), the Inventory isn't showing up. I've added Menu actions to show it, and tried to rebuild a couple times, without luck. Wondering if you have any tips for why this might be happening, and anything I can do to try fix it please?
I was previously messing around with using UnityUI for the Inventory, but since changed it back to an AC menu.
I also had an 'Inventory Pop' script attached to the PersistentEngine I think when I was using UnityUI, but have since removed that. I also had some issues with the Input System which I think I mostly resolved some time ago.
AC 1.85.1, Unity 6000.0.58f2
Edit: It doesn't work either if I change from AC to UnityUI for the Inventory.
This is my PersistentEngine:

Nothing unusual about my Inventory menu I don't think:

No inventory in Web build or Mac build:

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After some frantic messing around, I realised it was because I had 'Menu: Lock Inventory' in a previous scene that for some reason was letting the Inventory show up in the Unity Player but not in the build.
Leaving this thread here in case anyone pulls a similar smoothbrain move like me.