It belongs to the internal test function, and only some accounts can punch in. If you don't believe me, you can click on "My Card" with an account that can punch in, select a card with QQ growth experience and forward it to an account that can't punch in, and then click on the forwarded content with an account that can't punch in, and you can find the words "mysterious function test".

QQ is an instant messaging software launched by Tencent on 1999. It can not only chat and make friends on various communication terminals, but also make free video and voice calls, or send and receive important files anytime and anywhere. It can also communicate with mobile communication terminals, IP telephone networks, wireless paging and other communication methods. These powerful and practical functions make QQ a convenient and efficient instant messaging tool, not just a simple virtual pager.

QQ has covered many mainstream platforms such as Windows, Android and iOS, and is the most widely used communication software in China.