Removes the highlight around blocks in the Scratch editor when they run.
Download the code as a ZIP file then extract it. Go to Chrome extensions (chrome://extensions), enable Developer mode and press Load unpacked in the top-left corner. Select the folder with the extracted contents and you're good to go!
As long as you have it loaded, it will remove block highlights. If you want to disable it, go to Chrome extensions (chrome://extensions) and toggle it off from there.