How he made icon rendered into yaml?

Hello, I see in this post :

the guy setted a battery icon as prefix directly into yaml
I’d like to change this icon but i cannot find where it comes from and how to copy such icons to paste it into yaml.

how does it works please?

I have seen that as well - with a different icon. In my case it was one I wanted,. so I was able to just cut and paste. I would like to know however as well -
Copy and paste.

Thank you for this but I thought these .yaml files were always just text only! Great to copy and paste, but what exactly is it that is in my clipboard then? I’d like to create custom ones and understand better how they work - are they just jpg files or what?


Sorry for my late feedback.

Thank you @artpcpl , tested into notepad, it works fine.
You are the best !