Mac ONLY: Objects present in prefab, missing when prefab dragged to scene. Uh.... what?

I have a prefab in a Unity 2020.1.2f1 project. Inside that prefab are lots of different objects (models). There’s nothing clever or special about it; it’s just a game object with a bunch of positioned models inside.

On PC, everything works perfectly.

On Mac, half the contents are missing - but ONLY when the prefab is used in a scene.

To clarify: if I double-click to edit the prefab, all the models are there and visible, and I can ‘select’ them to trace them back to where they are in the project folder.

However, if I drag that exact same prefab into a scene, a whole bunch of the models don’t appear, and in their place in the hierarchy I get a load of ‘missing prefab’ entries.

I haven’t a Scooby what to do about this. It’s only on Mac - the project is an exact copy of the PC one (we use SVN and there are no local changes on the Mac vs PC).

…help?

NB: I know every horror story about meta files and source control. That isn’t it. All the meta files are present and correct, no conflicts, nothing generated twice on two machines.

Hmm. Okay. Well, despite SVN showing no differences, deleting the entire project folder and checking it back out from SVN fixed the problem. Hope that helps anyone in the same boat.

Hey, I came across the same problem, but on Windows.
I solve it by duplicating the prefab and replacing it in the scene.