Send epub to Kindle but don't keep the converted file?
I'm now proud owner of a Kindle and use Calibre to manage and convert my ebooks, which are mostly in epub format. I noticed, that when I send a book to the kindle, Calibre automatically stores the converted mobi file (I switched from azw3 because the the latest official release of the collection plugin doesn't work yet with azw3) alongside the original epub file.
I would rather have the conversion to happen in a temporary location to keep the collection free of format duplicates in the long run. How can I get Calibre to not save any converted file in my library upon sending to a device?