I'm confused why you said it like that, it's not like it's a well hidden secret. https://www.bilibili.com/
NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.
1 project | reddit.com/r/ChineseLanguage | 13 May 2022
Accessing Chinese based websites
1 project | reddit.com/r/ProtonVPN | 12 May 2022
1 project | reddit.com/r/u_Agitated-Health-8672 | 12 May 2022
1 project | reddit.com/r/u_Agitated-Health-8672 | 11 May 2022
How do you guys use Chinese in your life?
1 project | reddit.com/r/ChineseLanguage | 29 Apr 2022