By comparison, ByteDance’s Douyin short-video app counts 51 per cent of its users born after 1995, while the proportion of users under 21 years of age increased 13 per cent for QQ.

While WeChat allows users to select who they want share their posts with, the effort of grouping and then setting different permissions for each social circle is proving too much for an increasing number of mostly younger users.

China’s so-called Generation Z are instead migrating to other social media apps less popular with older adults, such as Douyin, the short-video app, or ironically, QQ, the grandaddy of messaging apps that was conceived originally for the personal computer era but has undergone a reincarnation of sorts to become a popular messaging tool for adolescents.

“Short videos have occupied more time of users and then they limited time on WeChat,” said Dingding Zhang, former head of Beijing-based research firm Sootoo Institute and now an independent internet industry commentator. “Young people prefer niche communication tools and the apps that their parents do not use to seek privacy and similar interests.”

WeChat did not respond to a request for comment.

The backlash against oversharing is part of a global trend. In 2018, more than three million people under 25 either quit or stopped regular use of Facebook, which has 2 billion registered users worldwide.

After WeChat released a function enabling users to restrict the visibility of their posts to within three days of the upload, more than 100 million users, or about a tenth of total users, used that setting as a default.

Retaining young users is crucial for WeChat, the dominant super-app in China that has become indispensable for everything from paying bills to booking hospital appointments.

Tencent needs to keep users on the WeChat platform so that it can cross-sell other services to its one billion daily active users. The growing question is whether WeChat has become too big for its own good, opening opportunities for more nimble providers to steal market share in their niches.

To be sure, WeChat is a formidable competitor. A trio of messaging challengers tried to upstage the incumbent last year and died a quick death as users found little incentive to leave WeChat’s ecosystem of more than two million mini-programs or apps-within-app for an unproven alternative.

WeChat also starves its competitors of traffic by blocking links that would direct users to these fledgling service providers, a practice that had competitors including ByteDance accuse the internet giant of monopolistic bullying, which Tencent has dismissed.

WeChat’s creator, Allen Zhang Xiaolong, described WeChat’s news feed-style function -Moments- as “an open square.” “When you post anything it is like talking aloud on the square,” Zhang said at the annual WeChat conference for developers and partners in Guangzhou in January. “You’ll have great pressure when you find many people on the square can hear you … and the pressure grows with the number of friends you have on WeChat.”

Qu Yao, 22, is finding it hard to juggle between her overlapping social and professional networks now that she has graduated and began working.

“When I want to share my personal thoughts and sometimes complain there, I have to block my family members, if not, they would nag about me,” said Qu, who lives in Beijing and works in an education institution. But if she wants to grumble about work, she has to block her colleagues and managers on WeChat, or risk torpedoing her career with an ill-considered post. “It is very annoying to have to group people and think about who can see my posts … Over time, I just quit sharing.”

Qu stopped sharing completely on WeChat after posting that she had ended her relationship after a quarrel with her boyfriend. While the two eventually made up, she was exhausted by having to explain to the army of parents, relatives and friends who swarmed her after the first post.

For Wang Jingyi, 14, a middle school student, posting to WeChat has invited unwelcome scrutiny from her parents. She had posted that she loves Hu Yitian, a popular Chinese actor.

“It annoyed me when my father commented on the post and said that I should study hard and not chase film stars,” said the teenager, who lives in Zhuji in Zhejiang province. “Our classmates have a WeChat group, but we did not talk for over a month.”

Ironically for a social media platform that aims to connect, many older adults are finding isolation from their children instead.

“From WeChat, I can know almost everything, except about my daughter,” said Wang, the 45-year-old stay-at-home mom. “I hope she can share her college life with me.”

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