Question about the relationship between marketplace and app visibility

Hi,

I was looking at the marketplace and noticed that there are apps with different visibility.

  1. public app
    • https://github.com/marketplace/codecov
    • https://github.com/apps/codecov
  2. private app
    • https://github.com/marketplace/zenhub
    • https://github.com/apps/zenhub
  3. 404 app
    • https://github.com/marketplace/codefactor
    • https://github.com/apps/codefactor

Question 1. Even if it is a private app, can it be published to the marketplace and can others install it?
Question 2. How do I set the app to 404?
Question 3. What is recommended: public, private, or 404?

Regards,

I solved it myself by contacting GitHub support.