Make it so the back:0 camera is the default to be turned on

I can hardly imagine a situation where you would want to scan a QR code with the front-facing camera. Yet, after having, for some reason, to give permission to use the camera for a dozen times, the front-facing one turned on. For a person with severe dysmorphia, unexpectedly seeing own face from such an unfortunately close angle was genuinely day-ruining.