the settings don't look like this anymore, any idea where the auto toggle smarti ui at H start button is now?F9 or "." on the number pad. You can also disable Smart UI in the kPlug options (red outline).
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As for disabling kPlug's FPV, I've occasionally ran into an issue where turning both options to OFF (highlighted in green) revert themselves back to ON the next time I load that save. I think changing the FPV/FOV options, saving, then restarting Koikatu keeps it disabled.