Here is more detail.
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I was not able to drill down on ebooks and images. I decided to delete them. You can see they are gone.
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And yet, they still show. I wanted to organize ebook files and ebook images. Since I could not drill down into ebooks and images to access my files, I uploaded the images and ebooks into media/files as you can see in the Publii file manager image above.
Since I can only upload 4 images, I will continue with another bug in my next post.