I’m pretty sure this highlighting is new and it’s been added in the last update (or the one previous.) In any case, I didn’t do it and I can’t figure out how to undo it or even use it for other sections. The sections in question are a copy and paste from a PDF version of the “Black Panther” script.
It’s not actually highlighting that I have access to unless there’s an option beyond the font background highlighting. And it doesn’t seem as if it’s a style of any sort. Even if change the style the blue highlighting stays on that section.
I’ve attached a screenshot.