Device: Kindle Paperwhite 4 (software up-to-date)
calibre 4.11.2
When I sideload .mobi ebooks from Project Gutenberg (
https://www.gutenberg.org), the changes I make to the metadata
do not appear on my Kindle, namely the titles and authors. That is, the old metadata appears on my Kindle, while the updated metadata appears on Calibre. However, covers that I generate (with the updated metadata)
do appear on my Kindle. Moreover, when I sideload .mobi ebooks from another website, the Internet Archive (
https://archive.org/index.php), the changes I make to the metadata
do appear on my Kindle. I note that I am doing any conversion and am saving to disk as a single file (Preferences > Saving books to disk > unchecked Save cover separately and unchecked Save metadata in a separate OPF file)
I am going crazy trying to understand why I can't edit Project Gutenberg ebooks specifically. Any help will be greatly appreciated.