Helping people with computers... one answer at a time.
"Secure and nonsecure" items is most often the result of bad web page design. As a user it's difficult to avoid without lowering your guard.
Can I get rid of the "This page contains both secure and nonsecure items" warning?
Not that I'm aware of, and not that I would want to. Not being notified is in fact a security risk when visiting sites you don't already know and trust. For the sites you do trust, the message results from bad site design on their part.
Thank you to a few readers who posted a solution to avoiding the warning: