Persistent Photos in news feeds
I have updated my Calibre to 7.15 and have experienced this issue. I do not know if it existed with previous Calibre versions since I have not had my program for very long and have not tried the news feeds before this point.
I have used the built-in Cbc.ca news feed and have found that if the news article has a photo in it, the photo stays on the Kobo screen with the text overlaying it as you read through the article. The first page looks fine; the text runs around the photo, but moving to the second page puts the new text right over the photo without removing the photo. It is possible to read the text over the photo, but it is really difficult. The photo stays at the top of the screen through the entire article.
This behaviour also happens in a custom recipe I created when a photo is part of the print version of the article I download. The recipe is simple, it gets the RSS feed and then pulls the print version of the articles.