How many "social accounts" icons can be shown on your Github bio?

Context

So, GitHub recently update the bio to have up to four social account links.

GitHub Social Icons

I tested many accounts, but only a couple of ones had an icon with it.
The rest, had the normal "chain icon" for links.

Question

So my question is: Has someone discovered how many links had an icon with it on GitHub social account links on bios?
Is there an post on GitHub Docs abou it?

Thanks in advance.

What have I tried

I got to GitHub Docs, but didn't found anything about it.

Also tried to search about it in other sources on the internet, same thing, no founds.

The currently supported networks are 8 traditional social networks:

1. Facebook
2. Instagram
3. LinkedIn
4. npm (missing from accepted answer)
5. Reddit
6. Twitch
7. X (formerly Twitter)
8. YouTube

Plus, 2 decentralised networks:

1. Mastodon
2. Hometown (Mastodon fork)

Whilst this information isn't documented anywhere on GitHub besides hints in release notes, you can find it yourself by viewing the source code of your GitHub profile and searching for data-provider-key. There will be duplicates (and the default generic), but all 10 will be there!

I also wrote a short script to extract all networks & regexes, but the information is all in the HTML.

Disclaimer: My article, but no ads / monetisation.