你知道吗？有的人笑的时候舌头是向上翘的

Meaning

Refers to the awkward chat behavior of asking if the other person has eaten. Originated from Bilibili UP "红烛Sakura"'s video "拦个女的折磨". In the video, during chat he suddenly asked "Have you eaten?" The girl asked "Why do you always ask people if they've eaten?" and the UP replied "民以食为天" (food is heaven for the people). Since then, "民以食为天" appears in danmaku when someone suddenly asks if the other has eaten.