how to handle kfx books in calibre?
['Update the Kindle App to the latest version. ... ', 'Update the Calibre to the latest version. ... ', 'Install the KFX Input plugin, by following the guide here.', 'Install the latest DeDRM 6.6. ... ', 'Download a Kindle ebook to your PC via Kindle App.', 'Drag the book into the Calibre.']