I ran into this problem while writing our Creating, Styling, and Validating Web Forms course. I was showing how browsers make an automatic request for “/favicon.ico” when first visiting a new site. However, once they’ve received the icon or determined it doesn’t exist, they don’t request it again on subsequent visits. That created a headache for me when trying to show how to deliver the icon. Unfortunately, it’s not easy to force the browser to refresh the favicon.ico, but it’s doable.