Serialized reference to prefab lost in build

We have a scene object with a script component that has a serialized field which contains a reference to a prefab. When this script attempts to Instantiate the prefab, a null reference exception is thrown. How can this be possible?

This reference is not null when playing in editor, nor is it null on 3 other platforms. We only have this problem on a single platform. The platform crashes shortly after this null reference exception is thrown, and I’m suspecting the exception is the cause.

This is happening shortly after a scene transition. The function in question gets called by an Awake event from another script. I have verified that the Awake function has ran on the script in question before this function call happens. So I don’t believe the function is called before the object loads, and I’m not confidant that would be a problem.

Asset bundles are being used in this project. However, I don’t know if that interacts with what is going on here.

I have tried reimporting assets. And I have verified by hand that the GUIDs in the YAML match between the reference in the component and the prefab.

This ended up being caused by a bug in Unity 2019.3.14 with asset bundles. We updated to 2019.4.11 and all the issues went away.