code block copy to clipboard button

**Is your feature request related to a problem? Please describe.**
I really would love to have a copy to clipboard button on every code block on the upper right/left corner.

**Describe the solution you'd like**
For example :o)
[prismjs - copy to clipbord](https://prismjs.com/plugins/copy-to-clipboard/)
[clipboardjs -smaller lightweight](https://clipboardjs.com/)

**Describe alternatives you've considered**
From [clipboardjs.com](https://clipboardjs.com)
A browser extension that adds a "copy to clipboard" button to every code block on GitHub, MDN, Gist, StackOverflow, StackExchange, npm, and even Medium.

Install for [Chrome](https://chrome.google.com/webstore/detail/codecopy/fkbfebkcoelajmhanocgppanfoojcdmg) and [Firefox](https://addons.mozilla.org/en-US/firefox/addon/codecopy/).