The words "trail on mouse" instantly reminded me of the Windows mouse trails, that's what I was expecting going into the article. But honestly, I really liked

The words "trail on mouse" instantly reminded me of the Windows mouse trails, that's what I was expecting going into the article. But honestly, I really liked whatever you call this type of trail. Not sure this was the intent, but I used the trail to trace under the lines as I reading them which helped me pay attention to the text a bit better. 100% agree with you on messing with selection and copy/paste though.