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+### Should I use Calibre?
+
+No. Calibre doesn't properly supported fixed layout EPUB/MOBI, so modifying KCC output in Calibre will break the formatting. On 7th gen and later Kindles running firmware 5.16.3+, you can get cover thumbnails simply by USB dropping into documents folder. On 6th gen and older, you can get cover thumbnails by keeping Kindle plugged in during conversion. If you are careful to not modify the file however, you can still use Calibre, but direct USB dropping is reccomended.
+
 ### General:
 * **All options have the additional description in a tooltip.**
 * Use high-quality source files. **It has a major impact on the final result.**