We as a kid making kite using toilet-roll thin cover-paper and bamboo sticks from mom’s bamboo sweeper 竹扫帚, nobody had ever discovered this trick!!

https://vt.tiktok.com/ZShRopefX/

He used GeoGebra tool to draw the animation geometry.

Proof:

https://en.m.wikipedia.org/wiki/Fermat_point