As self-described "TikTok refugees" pour onto the Chinese social media app RedNote, also known as Xiaohongshu, some foreign netizens are already running up against the country's extensive censorship apparatus.

With the U.S. ban on TikTok looming, many Americans are opting for another Chinese app known as RedNote. It could be short-lived.

Chinese social media app RedNote, known in China as Xiaohongshu, gained nearly 3 million U.S. users in one day earlier this week as a flood of self-proclaimed "TikTok Refugees" joined, according to new data from analytics firm Similarweb.