slideshows – Delete a slide from a notebook

A "slide" appeared in a notebook. How can I remove it. My solution was to copy the rest of the notebook and paste it into another notebook. I could not find any information about the slides in a notebook. The removal of the right hook did not work. I could not find a "gear". I do not know how it came about, probably a typing. The previous question had a bad screen capture and should be removed. I can not do that either?

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