I have found the plugin to convert to KFX, but I get an error:
calibre, version 5.8.1
ERROR: KFX conversion failed: <p><b>Cannot convert عالم صوفي</b><br><br><b>Conversion error:</b> Exception('Kindle Previewer 3 not installed as expected. (C:\\Users\\souto\\AppData\\Local\\Amazon\\Kindle Previewer 3 missing)')</p>
Any tips?
Cheers, Manuel