Who started “Dalgona coffee”?

뚤기ddulgi, on YouTube, Feb 22, 2020. It reached 7 platforms in 14 months.

LineageEach dot, 1,000 instagram #dalgonacoffee posts, approximatelyContestedKey steps, 12 of 17. Lines follow time and platform
KBS WORLD TVBefore the first post뚤기ddulgiFirst postPlatform jumpPlatform jumpOwner responsePlatform jumpPlatform jumpPressPeakCommercialAfterlifeBacklashPatient zero