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Front Brake Lights Could Drastically Diminish Road Accident Rates
(bioengineer.org)
This is a most excellent place for technology news and articles.
Those are typically DRLs. Chrysler did this for a while in the 2000s-2010s (maybe still, idk), where the high beam - in DRL mode - turns off while the turn signal is doing it's thing. Other manufacturers do this with dedicated DRLs, sometimes integrating the DRLs and turn signals into one multicolored unit (Kia Telluride, for example).
No manufacturer shuts off a headlight for a turn signal when the headlights are intentionally turned on (whether by light sensors at night, or by the driver).