Really strange PDF processing - you can't load a PDF and expect the add-on to read it. What you do is load a PDF, any PDF, then press the add-on icon. It says something about having to load the pdf, and presents a box to select file, after the file is selected, the PDF is opened in a DIFFERENT tab. So go back and close the original. Why, oh why ? why a second tab opened (since the big update), and why not work from a new empty tab from the start?