Which I now highlight to further play on your insecurities!
Seriously, look at how the highlight shows up in my response above. That’s pretty brilliant interface design. It’s like using a highlight marker and then scribbling your note in the blank space of a book.
The person responding can reference the passage by clicking on it in the box above, which makes it much easier to write a more detailed comment, instead of scrolling up and down to find the passage if they need to reread it.
And the writer sees exactly what the commentor is responding to, minimizing the confusion over the possible meaning of the response.
When someone just leaves a highlight, it’s short hand for “this is really good,” without wasting the time to write a response.