In the newest update, cameras which render to "Target Eye = None (Main Display)" seem to be broken
Example avatar id: avtr_2ec12510-58ac-4267-8890-8f1c7de58c43 - to reproduce, play VR and activate ShaderMotion -> Record from the radial menu.
Attached is an example of a Camera component which incorrectly causes the VR HMD to flip upside down.
It's not just avatars: I am able to confirm that some worlds are also broken.