The instructions below are not correct, or at least not specific. Hovering does absolutely nothing except cause the "Create an Image" button to appear. If you click on the image *anywhere other than the "Create an Image" button, it opens a screen to left where you can edit some info about the file. Given that you have just done what it said to do - hover - and then clicked logically on the image - after all, if you hover on the image, you should be able to click the image - one then assumes that the file info you are editing is about the image you have just created (or so one would believe). Actually, you're just editing info about the uploaded file, and you have done nothing about creating an image. So... the instructions need to say something like "Hover on the PDF image below and then CLICK the "Create an Image" button."
