Simple and works well

This is an excellent companion to the native code block in WordPress. It adds a code button inside the code block, which I prefer so it doesn’t take up too much room. I had to add some CSS overrides in my theme to maintain the appearance of my code block style, and to move the button to the far right of the block where I wanted it. I’m giving it 4 stars because of that, but I otherwise would have given it 5 stars for ease of use.

/* Removes 50px padding added by the plugin's CSS */
.code-block-wrapper { padding-right: 0 !important; }

/* Forces the button to move to the right after removing the 50px padding */
.copy-code-btn { right:4px !important; }