I rly can't figure it out and I'm literally at the pressing random buttons phase of struggling with computer because nothing I've found online has helped and I don't know what I'm doing, so if you have any ideas please let me know.
the head bone and a couple other spine bones had a roll of 90.0001d which I didn't notice because blender doesn't indicate that there's a decimal point if it's tiny..... and changing that caused the fbx to import into Unity without the fucked up head - but - not - eyes rotation
