Depending on the firmware version, the name may appear under Ambient Filmmaker Mode or Adaptive Filmmaker Mode, but the function remains the same.
Once enabled, the adjustment is fully automatic. During the day, when natural light fills the room, the TV slightly increases the luminance to prevent shadow details from disappearing. When night falls, the mode returns to its original curve, calibrated for darkness. And in an already dark room, the sensor does not change anything, the rendering remains unchanged.
Tip: to notice the difference, test a dark scene (like those in Blade Runner 2049 Or The Batman) during the day, alternating between classic Filmmaker Mode and Ambient. The difference is obvious.