First paragraph highlighted when switching documents

When I switch from one document to another, the first paragraph or so is highlighted. Sometimes it is only one sentence, sometimes it is more than a paragraph. This highlighting doesn’t happen every time I switch documents, but most of the time it does. I’ve noticed that if I clear the highlights during a session, then go back to that document, the highlights are still cleared. However, if I close Scrivener and reopen, the highlights return upon switching documents.

Note: This is text that I have never manually highlighted before, so it’s not that the program is remembering the highlights. Also, it’s only the top paragraph that is viewed currently on the screen, not the first paragraph of the document.