Twitter validator cards

How does twitter show those link cards when you add a link?

Under the Hood
I was wondering how Twitter shows the link cards whenever we add links in the tweet input. So after researching a bit I found the Twitter process and how we can build something like that on our own.

But I will not cover this in the text format instead I will share the information via video. Here is the video link, if you like the video please do show some support.

Video link

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