I’m somewhat surprised that there is no answer so far, because that really seems to be bug.
As the thread opener said, there is no difference between what I suppose are the automatic and the manual flash modes. In auto mode (with the red dot on the red flash icon), the flashlight is on all the time. In manual flash mode (red flash icon without dot), the flash is not on permanently, but it fires up on each photo taken, no matter how dark or bright the surrounding light conditions are.
The expected behaviour of an auto flash mode is that it fires up upon taking a photo when it’s dark, and to not fire up when it’s bright. This is how auto flash works on ALL phones that I know.
On the front facing cam, both flash modes work as expected, despite the obvious fact that there is no actual flash LED but only a simulation by brighting up the display.
Are we doing something wrong?