>>84159203It's a number of symbolic gestures done by a subjugated populace in order to force them to admit inferiority to a superior.
The term came from Maoist China after the Great Leap Forward where the undesirables were publicly shamed by friends, family, disowned and ostracized before stadiums of people before being executed to destroy not just their body but their name and memory.
Now it just means "I saw something I don't like on the internet".