Cool, thanks! I'm new to this extension, and it took me a while to figure out that I had to add the toolbar button. Once I got that, the whole thing was a breeze. I especially like how you use the API instead of just storing the username/password (vulnerable) and "scraping" off the website.
Since I have ~50 books in my Calibre library, it took a while to link every book. It's not a big deal though, since I only have to do it once. However, if you want to fix the problem, I suggest that you instead have one main window that lists all the books that I selected. Books that yield one result are auto-selected, so that people will only have to fine-tune their books that have many different search results. (If that makes any sense
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