How to take a screenshot with transparent background (opacity)

Not sure if it's the right place to ask, but I'm wondering how to take a screen shot with a transparent background. I've got a one like below. https://preview.redd.it/fx1h3yup6ohe1.png?width=1460&format=png&auto=webp&s=facd6df47aea6b82a0af2c00629e4854803e574f But If I take a screenshot in the whole screen, it should look like this. https://preview.redd.it/n97l408s6ohe1.png?width=2940&format=png&auto=webp&s=65b47d6267e726c891c0f01fd07da881ded0d620 So how should I got what I want. Thanks for helping btw.